Thursday, February 21, 2013

Noë on the origin of life etc.


UC Berkeley philosopher (and atheist) Alva Noë is, as we saw not too long ago, among the more perceptive and interesting critics of Thomas Nagel’s Mind and Cosmos.  In a recent brief follow-up post, Noë revisits the controversy over Nagel’s book, focusing on the question of the origin of life.  Endorsing some remarks made by philosopher of biology Peter Godfrey-Smith, Noë holds that while we have a good idea of how species originate, there is no plausible existing scientific explanation of how life arose in the first place:

This is probably not, I would say, due to the fact that the relevant events happened a long time ago.  Our problem isn't merely historical in nature, that is.  If that were all that was at stake, then we might expect that, now at least, we would be able to make life in a test tube.  But we can't do that.  We don't know how.

But it is worse than that, in Noë’s view.  He holds that we also do not even know whether such an explanation is just around the corner, or instead will require a scientific revolution, or, alternatively, will turn out to be impossible in principle. 

Something similar can be said, in his view, of the question of whether science can explain intelligence:

If we really understood what makes a person intelligent, then it ought to be relatively straight forward, at least in principle, to manufacture intelligence.  Some people believe that this is possible.  Others that we can actually make intelligent machines and robots now.  I do not suppose that they are wrong. But I do take it as manifest that we do not know this to be the case.  Many mainstream scientists and philosophers believe that true artificial intelligence is at best unfinished business.

With respect to both controversies -- the origin of life and the nature of intelligence -- Noë writes:

What kind of disagreement is this?  To my mind it is foolish to cast it as a standoff between those who embrace science and admit its stunning achievements and those who reject the project of natural science itself.  It is not a conflict between those who know and those who are confused.  Some critics of Nagel's book adopt this pose, as if this were some kind of episode in our culture wars…

The issue at stake is internal to science.  We have not yet integrated an account of ourselves into our understanding of nature.  And so our conception of nature itself is, or threatens to be, incomplete.

End quote.  In my earlier post on Noë I noted that he also holds that “we haven't a clue” how “consciousness [emerges] from the behavior of mere matter.”  The issue here, of course, concerns what David Chalmers calls the “hard problem” of consciousness -- the problem of explaining why the neural processes that underlie perception, behavior, etc., are associated with qualia, those aspects of a conscious experience directly knowable only from the subjective or “first person” point of view.

Life, consciousness, intelligence -- is there anything significant about that particular triad?  There is.  It corresponds more or less exactly to the traditional Aristotelian distinction between the three fundamental forms of life: vegetative, sensory, and rational

“Vegetative” life as Aristotelians use that term -- and it is a technical, metaphysical usage, which is not meant to correspond exactly to the way the term is used is ordinary language or contemporary biology -- is any sort of life that exhibits the basic functions of life but nothing more.  Those basic functions include nutrition, growth, and reproduction, where these are taken to be “immanent” activities in the sense that they terminate in and promote the flourishing of the whole substance that carries them out.  “Immanent” causation is in this context contrasted by Aristotelians with “transeunt” or “transient” casual processes, which terminate outside the agent.  Digestion would be an example of an immanent causal process; one billiard ball causing another to move would be an example of a transeunt causal process.  For Aristotelians, the essential difference between living and non-living things is that living things are capable of both immanent and transeunt causation, whereas non-living things exhibit only transeunt causation.  And nutrition, growth, and reproduction constitute the basic package of immanent activities.

(I say more about this at pp. 132-138 of Aquinas and in some earlier posts about the nature and origins of life, here, here, and here.  For a lengthier recent defense of the Aristotelian account of the nature of life, see David Oderberg’s Real Essentialism.)

Sensory life is the sort had by living things that not only carry out the activities characteristic of “vegetative” life, but, on top of that, possess sensation, appetite, and locomotion.  Sensation involves the capacity to take in information from the surrounding environment via specialized organs (such as eyes, ears, skin that is sensitive to temperature, and the like).  Appetite involves the formation of inner impulses in response to what is sensed, and locomotion involves self-movement that is prompted by the appetitive impulses so as to take the living thing that has them either toward or away from the sensed objects that generated the appetites in question.  This package of capacities is, on the traditional Aristotelian view, essentially what distinguishes animals from plants, though there could of course be debate over whether some particular living thing is best understood as falling into the “vegetative” or the “sensory” category (see Oderberg for discussion).  But that the distinction between vegetative and sensory forms of life really is a distinction in kind and not degree is evidenced by the persistence of the qualia problem.  For the possession of qualia is an essential part of what it is to have the sensory and appetitive capacities that animals exhibit and plants evidently do not.  (I’ve said more about this distinction here and here.)

Rational life, as Aristotelians understand it, is the kind had by living things that possess not only the characteristics typical of vegetative and sensory life -- nutrition, growth, reproduction, sensation, appetite, and locomotion -- but, on top of that, intellect and will.  Intellect involves the ability to grasp abstract concepts (such as the concepts man and mortal), to put them together into complete thoughts or judgments (such as the judgment that All men are mortal), and to reason from one judgment to another in accordance with logical principles (as we do when we reason from the premises that All men are mortal and Socrates is a man to the conclusion that Socrates is mortal).   Behavior that results from will or free choice is behavior that follows from reason rather than merely from the impulses of appetite.

The Aristotelian holds that, just as sensory life differs in kind and not merely degree from merely vegetative life, so too does truly intellectual activity differ in kind and not merely degree from the sort of which mere sensory forms of life are capable.  Indeed, the divide between the truly rational and the merely sensory forms of life is especially radical insofar as strictly intellectual activity (unlike sensory activity) is essentially incorporeal and cannot in principle be entirely reduced to the activity of any bodily organ.  I’ve discussed the reasons in many places, such as in Aquinas, but the most detailed treatment can be found in my new ACPQ article “Kripke, Ross, and the Immaterial Aspects of Thought.”

For the Aristotelian, then, there are three radical “jumps” in nature -- the jump from inorganic phenomena to the basic, “vegetative” forms of life (i.e. the sort that exhibit the basic package of “immanent” as opposed to merely “transeunt” activities); the jump from merely “vegetative” forms of life to sensory forms of life (i.e. the sort that possess qualia); and the jump from merely sensory forms of life to rational forms of life (i.e. those with the strictly intellectual capacities that presuppose the possession of abstract concepts).  When I speak of a “jump,” though, it is important to emphasize that what I primarily have in mind is something ontological rather than temporal.  For the Aristotelian, questions of metaphysics (what a thing is) are more fundamental than, and to be settled prior to, questions of historical origin (where a thing came from).  Indeed, at least where we have no independent evidence of origins, we cannot fruitfully address the question of where a thing came from before settling the question of what it is, since only when we know its nature will we know what its possible sources might be. 

It is thus sheer, question-begging dogmatism for naturalists to insist that some phenomenon P -- where P is life, say, or intelligence -- simply “must” be purely material because we “know” P could only have had material origins.  If we have no direct evidence whatsoever of P’s origins (as is the case with life and intelligence, since no one has ever observed living things arising from entirely inorganic causes, or an intelligent creature arising from entirely non-intelligent causes), then we have to look to P’s nature to begin our investigation of what its causes might have been.  And if an investigation of its nature shows that it is not entirely material -- as an investigation of the nature of intelligence shows that it cannot be entirely material even in principle (again, see the ACPQ article referred to above) -- then we know that its causes cannot have been entirely material.

How, then, does the Aristotelian position relate to evolution?  The answer is complicated.  On the one hand, the Aristotelian obviously rejects the materialist conception of matter associated with contemporary naturalism -- a conception on which the material world is devoid of any immanent teleology or immanent natures (i.e. final causes and substantial forms).  On the other hand, nothing that has been said above has anything to do with “specified complexity,” probabilities, “gods of the gaps,” or any of the other themes of “Intelligent Design” theory and William Paley-style design arguments.  On the contrary, Aristotelians and Thomists are often extremely critical of ID and of Paley (as I have been in a series of posts).  And part of the reason is that ID is simply not radical enough in its critique of naturalism, but implicitly buys into the same false conception of nature to which the materialist is committed, and thereby merely muddies the conceptual waters. 

Moreover, modern Aristotelians (such as the Neo-Scholastic writers of the early twentieth century) are not necessarily opposed to evolutionary explanations as such.  They do agree, though, that such explanations have limits, and would by no means give a blank check to Darwinian naturalism.  And those limits are limits in principle (not mere matters of “probability”) because they have to do with metaphysical divisions in nature (not mere differences in the degree of “complexity” of the arrangement of mechanical parts or the like).  I have discussed the Aristotelian-Thomistic approach to the origins of life here, and the question of human origins here and here.

In any event, it is certainly telling that, although it is part of the modern conventional wisdom that the traditional Aristotelian distinction between vegetative, sensory, and rational forms of life is a historical relic, we have a mainstream, atheist philosopher like Alva Noë essentially admitting that the explanation of each of these forms of life in terms of something more basic is, even in AD 2013, still highly problematic.  And as I pointed out in my First Things review of Mind and Cosmos, Nagel -- another mainstream atheist philosopher -- essentially says the same thing about each of these traditional Aristotelian categories.  Various other prominent contemporary atheists and naturalists -- Jerry Fodor, John Searle, David Chalmers, and many others -- have acknowledged that at least one or two of these categories remain problematic.  And of course, as I noted in an earlier post on Nagel, renewed interest in Aristotelian themes can be found in much contemporary mainstream work in other contexts, such as metaphysics, philosophy of science, and ethics.  

Could someone not self-consciously Aristotelian or Thomist sound more Aristotelian than Noë already does?  Turns out he can.  Consider some remarks he made in the interview linked to above:

For a long time now, going back at least to Descartes and Galileo, we’ve liked to be told that things are not what they seem.  When we go to a magic show, there’s a feeling of delicious pleasure when the wool has been pulled over our eyes.  Similarly, to be told that the love you feel is actually just a chemical reaction, or that your depression is just a malfunctioning of your brain, is surprising and in some paradoxical way satisfying. There’s a modern pleasure in the unmasking of our everyday experience.  We feel like we’re seeing behind the curtain, seeing how the trick is done…

Galileo said that the apple in your hand is colorless, odorless and flavorless.  That color and so on are effects that the apple has on you, comparable to the sensation of the prick of a pin.  The flavor of the apple, he said, is no more in the apple than the prickliness is in the pin.  The taste and the prickliness are in you.  Galileo thought we were radically deceived by the world around us.  The contemporary neuroscientists simply extend this even further — this idea that the world is a kind of grand illusion that the brain creates.

Sure, it’s an important fact that the perception of colors depends on the physics of light and the nature of the nervous system.  If our physiology were different, our ability to detect colors would be different.  But none of that speaks to the unreality of color, any more than saying that I can’t see anything in my room if I turn the lights off speaks to the unreality of my desk.  We’ve almost made a fetish of this desire to be told that things are not what they seem.  We get a thrill from the paradox.

End quote.  Noë is particularly critical of reductionist accounts of human nature:

Trying to understand consciousness in neural terms alone is like trying to understand a car driving down the road only in terms of its engine.  It’s bad philosophy masquerading as science…

The brain is necessary for consciousness.  Of course!  Just as an engine is necessary in a car.  But an engine doesn’t “give rise” to driving; driving isn’t something that happens inside the engine.  The engine contributes to the car’s ability to drive.  Consciousness is more like driving than our philosophical tradition leads us to expect.  To be conscious is to have a world.  The fact is, you and I don’t have what it takes to make a world on our own.  We find the world, we don’t make it in our brains.

The brain is essential for our lives, physiology, health and experience.  But the idea that it is the whole story, or even the key to understanding the story, is not a scientific conclusion.  It’s a prejudice.  Consciousness requires the joint operation of the brain, the body and the world.

End quote.  What Noë is here decrying is, essentially, what I have described elsewhere as scientism’s tendency to reify abstractions and to treat parts of substances as if they were substances in their own right, and his examples are more or less the same as the ones I gave there.  From the rich, concrete world of material objects presented to us in experience, which is characterized by colors, sounds, odors, flavors, warmth, coolness, meanings and purposes, causal powers and liabilities, physics abstracts out its mathematical structure.  That is extremely useful for certain purposes and certainly captures aspects of what is really out there in the world.  But scientism treats this abstraction as if it were the concrete reality itself, and the entirety of that reality.  From concrete human beings, neuroscience abstracts out the nervous system and makes of it the focus of study.  This too is useful for certain purposes, and is unproblematic as long as it is kept in mind that neural structures and processes can properly be understood only by reference to the whole organism of which they are a part.  Scientism, however, fallaciously tends to treat such structures and processes as if they were substances in their own right, and attributes to them activities -- “interpreting,” “perceiving,” “deciding,” etc. -- that can intelligibly be attributed only to the human being as a whole and not to any part, not even a neurological part.  (I’ve discussed various “neurofallacies” at greater length here and here.)

Scientism claims to be “reality based” but that is precisely what it is not.  It recognizes only aspects of reality, and in particular only those susceptible of study via its favored methods.   When those methods fail to capture some aspect of reality -- God, consciousness, intentionality, free will, selfhood, moral value, and so on -- scientism tends to blame reality rather than its methods, and to insist that the reality either be redefined so as to make it compatible with its methods, or eliminated entirely.

The Aristotelian, by contrast, insists upon recognizing the world as it really is, and adjusting method to reality rather than reality to method.  Hence while the methods appropriate to physics -- the construction of mathematical models that capture those aspects of material nature susceptible of strict prediction and control -- are certainly suitable for the study of some phenomena, they are not suitable for biology, psychology, ethics, metaphysics, or what have you.

As we’ve seen, in his most recent post, Noë writes:

The issue at stake is internal to science.  We have not yet integrated an account of ourselves into our understanding of nature.  And so our conception of nature itself is, or threatens to be, incomplete.

But the Aristotelian-Scholastic tradition had an account that integrated us into nature.  It is scientism, which abstracts out of nature everything that smacks of the human, that has created the problem of reintegrating us into it.  The solution is not a further application of its methods, which simply compounds the problem, but a realization that those methods are not the only ones available to us, and never were.  The work of Nagel, Noë, and Co. is evidence that that realization is increasingly to be found outside the circle of self-consciously Aristotelian and Thomistic philosophers. 

120 comments:

  1. Doctor, I have always wondered what went on in western philosophical community, why has scientism become so common, it is taken by most people who love science to be a given, to the point they get baffled to see people that like science but won't endorse scientism, and I've seen my share of scientists who think like that....

    So exactly.... How we came to this point?

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  2. why has scientism become so common, it is taken by most people who love science to be a given

    Because people have always needed authority figures to cling to, look to and quote. Especially authority figures who deal in important subjects they do not understand, or care to understand.

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  3. Could it be all? Just our need for a leader? Lack of intellectual independence?

    I mean I obviously agree that we the people are overall intellectually lazy and many intellectual groups are formed in search of a leader to guide the pupils, but I wonder if there was any other factor that contributed.

    You know... Like positivism...

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  4. My own sheerly gratuitous theory is that the Platonic defenses of atheism came to be seen as inadequate and naturalism/physicalism came to be seen as a last redoubt (or at least the next one). That's a cheap shot though, so here's a more generous one: science works really, really well and tells us lots of awesome stuff about the universe. It's not totally insane to start to think it might do more...it's just insane to stick with it once it's shown not to do so.

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  5. I've heard it put this way: It all began in a garden. At the centre of the garden was the tree of life. People were tempted to turn away from life by the pleasing-to-the-eye appearances of the fruit from the tree of knowledge. The temptation has been there ever since to put knowledge before life.

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  6. Feser: "Those basic functions include nutrition, growth, and reproduction, where these are taken to be “immanent” activities in the sense that they terminate in and promote the flourishing of the whole substance that carries them out. “Immanent” causation is in this context contrasted by Aristotelians with “transeunt” or “transient” casual processes, which terminate outside the agent. Digestion would be an example of an immanent causal process; one billiard ball causing another to move would be an example of a transeunt causal process."

    As a side note, Aquinas thinks it is possible for a demon or angel to cause an assumed body to exercise transeunt operations but not immanent ones. The angel or demon can thus cause the body to simulate speech or consumption of food, but these will be merely transeunt analogs of the real thing. I guess that would be kind of like artificial intelligence? (Cf. De potentia 6.8)

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  7. I wonder about the jump from sensory to rational. There are animals and birds with basic reasoning ability, number sense, and even basic morality. It may be that there is such a jump, but at first glance it doesn't appear to be so. I'd advise looking into the science on this, in a serious way.

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  8. The sensory being includes the inner senses of common sense, memory, and imagination. Common sense is what combines the disparate channels of sight, sound, taste, etc. (which actually reach the brain split seconds apart) into a common ymago. Memory is the storage of these ymagos, and imagination is the ability to recall and manipulate them. (That is, the memory of a red ball can be recalled and imagined as a blue ball.) The whole shtick can be lumped under a broader meaning of "imagination" (namely, the care and feeding of images). Consequently, anything with imagination can simulate much of what passes as intellection. The ability to count real things belongs to imagination. The ability to carry out mathematics is a different kind of activity. The same applies to "reasoning" with respect to actual sensory objects as opposed to reasoning about abstractions. A bird may recognize three orange seeds (and may remember having seen three orange seeds in a particular place and therefore look there again in search of seeds; thus, performing re-search) but it does not know what "three" is, or "orange" or "seeds." Aristotle said that an animal "knows flesh" but does not know what flesh is.

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  9. The idea that scientism arose from the need for authority figures is laughable, however pitiful you may find scientism. E.A. Burtt's 'The Metaphysical Foundations of Modern Science' provides an actual historical and philosophical picture of what happened. Suffice to say that the story is just •slightly• more complicated.

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  10. Anonymous said...

    The idea that scientism arose from the need for authority figures is laughable, however pitiful you may find scientism. E.A. Burtt's 'The Metaphysical Foundations of Modern Science' provides an actual historical and philosophical picture of what happened. Suffice to say that the story is just •slightly• more complicated.
    February 22, 2013 at 10:16 AM "



    If you are willing to outline Burtt's argument on this development, it would be helpful.

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  11. " Eduardo said...

    Could it be all? Just our need for a leader? Lack of intellectual independence?

    I mean I obviously agree that we the people are overall intellectually lazy and many intellectual groups are formed in search of a leader to guide the pupils, but I wonder if there was any other factor that contributed.

    You know... Like positivism...

    February 22, 2013 at 5:43 AM"


    If you are questioning the psychological impulses or motivations as much as some pure logical impulsion generated by the intellectual conviction that certain propositions are true, your reference to positivism, probably points the way to part of the answer.

    I've linked to it before so I won't do it again, but there is a phenomenally revealing, and honest moment, in A.J. Ayer's discussion with Bryan Magee during the Men of Ideas series. As I recall, Ayer frankly admits that the agenda was exciting, felt liberating, was socially or politically motivated in measure, and was when taken literally, false.

    It can still be found on Youtube.


    Ok. I'll link ...http://www.youtube.com/watch?v=4cnRJGs08hE&feature=player_detailpage&list=PL27237BEACE46EC46#t=380s

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  12. "If you are willing to outline Burtt's argument on this development, it would be helpful."

    Yikes - there are a lot of historical developments running from Descartes to Newton (Burtt ends with Newton; Darwin is also highly relevant) to account for. But, hopefully, a condensed version would go something like this:

    The categories of what constituted reality changed from largely Aristotelean metaphysical categories (forms, etc.) to mathematically quantifiable categories such as space, time, mass, force, etc. So reality became 'ultimately' mathematical - mathematical reductions became 'true' explanations. Metaphysical issues were either avoided (Newton's dismissal of 'hypotheses', for example) or simply loosely ascribed to God. (Physical reduction to parts - atoms, for example - was also important in this historical change.)

    Formal and final causes were dismissed as so much hot air or pointless speculation, in favor of efficient causes which could be demonstrated experimentally. So experiment became the superior means for demonstrating truth/reality. 'Hypotheses' (including any metaphysical speculations) that couldn't be demonstrated experimentally were seen as, at best, provisional.

    Qualia such as color, taste, etc., as noted in the OP, became unreal because they couldn't be mathematically reduced - they were 'mere' products or creations of the human mind with no 'ultimate' reality. So mind was separated from the material world - I can't quite remember which early modern scientists it was, but some even placed the soul strictly within the confines of the skull; it became, despite being immaterial, 'trapped' in the body. There may even have been some who believed that it might be composed of atoms...again, I'm foggy on that.

    There's more to it, but hopefully the above is a not-too-botched summary of the larger changes. From the above I think you can see the general arguments of modern scientism - reductionism, experiment (Hawkings' 'science will win because it works'), epistemology over metaphysics, etc.

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  13. Actually, above when I said 'running from Descartes to Newton', I omitted Copernicus, Galileo, Kepler. Not sure why I skipped them and started with Descartes....

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  14. The problem is that sensation can not simply be reduced to a material matter. Proof: understanding a form, like triangularity does not make you take on a triangular shape. So we know that the intellect must hold forms in a way that is not material, and so that the intellect itself can not be material. But in the same way perceiving something red does not turn part of your brain red, or something soft does not make your brain soft. Therefore qualia also can not be sensed in a material way, and there must be something immaterial about animals to perceive qualia. Or else animals do not perceive them in the way that we do.

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  15. Hi Ed,

    Thanks for an interesting and informative article. I have to take issue with you on one point though, and that's consciousness. You suggest that it coincides with the emergence of the Aristotelian sensory soul. I did my thesis on animal minds, and I've read a lot of the scientific literature on consciousness. The conclusion I've come to is that while a strong case can be made for the occurrence of phenomenal consciousness - which I argue in my thesis is roughly equivalent to what neuroscientists call primary consciousness - in mammals and birds, it is almost certain that other animals are not conscious in this sense. (Octopuses are the only possible exception.) See this paper:

    Rose, J. D., Arlinghaus, R., Cooke, S. J., Diggles, B. K., Sawynok, W., Stevens, E. D. and Wynne, C. D. L. (2012), "Can fish really feel pain?" (Fish and Fisheries, doi: 10.1111/faf.12010). A copy is available here: http://www.vapaa-ajankalastaja.fi/files/Tiedostot/RoseEtAl_FishFish_online_2012.pdf .

    I discuss the question of which animals have senses in great detail in my thesis at http://www.angelfire.com/linux/vjtorley/Anatomy.pdf , pages 163 to 178. The conclusion I reach is that in a very broad sense, all cellular life-forms (including bacteria) have sensory capacities of some sort, but that true senses are confined to organisms with nervous systems, which most animals have - including jellyfish but not sponges. These animals can be said to have access consciousness, but not phenomenal consciousness.

    In other words, about 99.8% of the 7.7 million-plus species of animals don't experience qualia or suffer pain, even though they can sense objects in their environment.

    I'm a little puzzled by your assertion that colors are in things. Now, if you'd said that colors result from the interaction of things with the sensory organs of sentient beings, I'd have no trouble understanding you, but what can you mean when you claim that, for example, the yellowness of a lemon is in the lemon? And which yellowness would that be - the one I see or the slightly different yellowness that you see? Just asking.

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  16. "The categories of what constituted reality changed from largely Aristotelean metaphysical categories (forms, etc.) to mathematically quantifiable categories such as space, time, mass, force, etc. So reality became 'ultimately' mathematical - mathematical reductions became 'true' explanations. Metaphysical issues were either avoided (Newton's dismissal of 'hypotheses', for example) or simply loosely ascribed to God. (Physical reduction to parts - atoms, for example - was also important in this historical change.)" -- While that may be true, it certainly doesn't constitute a real explanation. I'd have thought you'd more helpfully look at Francis Bacon for that.

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  17. So it was all just a major metaphysical change, which agrees with what Feser usually says it happened. But it makes no sense to turn a method into an stargate to reality, unlesss...

    Anyways I think DNW got my question better...

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  18. "what can you mean when you claim that, for example, the yellowness of a lemon is in the lemon? And which yellowness would that be - the one I see or the slightly different yellowness that you see?" -- Funny question! IF the yellow is in the lemon, then the yellow that you and Ed see (the yellow's intentional being) is in each case caused by the lemon's yellowness (the yellow's natural being). Whether the intentional being in you is entirely identical to that in Ed is irrelevant to the claim about the primary locus of the color itself being in the natural extramental thing.

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  19. Lol, hey Reighley wanna discuss explanations again? XD

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  20. "A bird may recognize three orange seeds (...) but it does not know what 'three' is, or 'orange' or 'seeds.'"

    Then how could the famous Alex the parrot respond to questions like "How many orange seeds?", when presented with a novel collection of objects, with unfamiliar people asking the question, and correctly answer that there are three?

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  21. Anonymous said...

    "If you are willing to outline Burtt's argument on this development, it would be helpful."

    Yikes - there are a lot of historical developments running from Descartes to Newton (Burtt ends with Newton; Darwin is also highly relevant) to account for. But, hopefully, a condensed version would go something like this:

    The categories of what constituted reality changed from largely Aristotelean metaphysical categories (forms, etc.) to mathematically quantifiable categories such as space, time, mass, force, etc. So reality became 'ultimately' mathematical - mathematical reductions became 'true' explanations. Metaphysical issues were either avoided (Newton's dismissal of 'hypotheses', for example) or simply loosely ascribed to God. (Physical reduction to parts - atoms, for example - was also important in this historical change.) ..."


    Ok, in measure he's reciting the now more or less standard history of modern science themes we are all familiar with from our Dover series reprints. e.g. Crombie, A. C. The History of Science from Augustine to Galileo.

    However Burtt may have been an interpretive leader in that area.

    I only have his "Right Thinking" logic text (which was the one my father used in the 50's). And what is remarkable about that book, is the enormous effort he puts into a scheme trying to salvage value statements as objective on some pragmatic basis which question beggingly assumes the value of democratic consensus. Apparently WWII jolted his prewar cynicism regarding the possibility - or necessity - of grounding value statements as more than subjective expressions of preference.

    His argument, though much more convoluted and developed, is thematically something like Sam Harris' line of attack. Maybe Harris' father or grandfather used the same text. LOL

    Speaking of Crombie, he makes much of Galileo's Platonism.

    I haven't read enough of Galileo's work to know if the argument is well founded or not. But it's clear that Crombie is not buying the usual stage play type storyline.

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  22. DavidM,

    You write that the primary locus of the color itself is in the natural extra-mental thing. (For the yellowness of a lemon, that's the yellow's natural being.) You also write that the yellow Ed sees and the yellow I see are both caused by the lemon's natural color. OK. What color is that?

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  23. "You also write that the yellow Ed sees and the yellow I see are both caused by the lemon's natural color. OK. What color is that?" -- Yellow. (I get the sense this must be a trick question.)

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  24. Prof. Feser,

    Great post, thank you.

    Question: Will your ACPQ article be available for free at some point? Or should I just suck it up and pay the $20?

    I mean, I'm sure it is worth the $20, but I paid less than that for three of your full-length books :).

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  25. Let me ask the question for torley...

    DavidM, the color yellow that I see is not, in terms of experience, identical to the yellow Ed sees.

    So which one is seeing the right color given that we can't both be right?

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  26. David M,

    Which yellow?

    http://kremerpigments.com/shopus/Media/Shop/fk-gelb-m.jpg

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  27. "Which yellow?" Lemon yellow (#23310).

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  28. This is something I've been wondering about for a while: How are sensations and mental images (i.e. the internal images that go along with thoughts) supposed to be material in an Aristotelian view? I mean, it's not like you can *see* mental images in someone's brain (all you see is electricity and chemicals as far as I'm aware), so how can these mental images be "material" (unless A-T doesn't require something to be publicly observable to qualify as material)?

    This is probably the biggest obstacle to me accepting hylemorphic dualism over Cartesian substance dualism. Treating internal mental images as "material" when they are clearly not observable in the brain doesn't make sense to me, and I'm not sure if that's a misunderstanding on my part or if the definition of "material" is that much different in A-T than it is in modern philosophy.

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  29. @ BURTT's Anon

    I think my man, you have actually unwantedly agree to Authority Anon. Are you not saying that as intellectual groups people have followed the great metaphysical of the great minds in the past???

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  30. DNW...

    I think it is about time we create... a new society filled with poneys and escape this worthless reality don't you agree ????

    O_O AGREEEE!

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  31. DavidM,

    I think I see the problem. You've defined color as something non-phenomenal. But if it's something you can point to out there, then it's not a phenomenon. All you're saying, then, is that lemons have a built-in tendency to cause qualia. Sure. But people can and do disagree about where the boundaries of colors end. This suggests that they see things differently. How a person sees something is what I call color. And that's not the same for everyone, whereas the lemon's (mind-independent) tendency to cause qualia is, because it's in the lemon itself.

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  32. "You've defined color as something non-phenomenal." -- No, certainy not!

    "But if it's something you can point to out there, then it's not a phenomenon." -- Only if that's how you define phenomenon. I say that a phenomenon is that which appears and that that which appears is something out there that I can point to.

    "All you're saying, then, is that lemons have a built-in tendency to cause qualia." -- I'm saying lemons are yellow, i.e., they are *visible*. Part of being yellow is having the capacity to be seen. And the action of being seen is more properly located in the patient (the sensory faculty) than in the agent. Color - the object of sight - is more properly located in the natural colored thing.

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  33. Eduardo: "So which one is seeing the right color given that we can't both be right?" - Why do you assume that you are not both seeing 'the right color'? Does one of you have impaired vision?

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  34. Probably the same way that Hans the Horse could do arithmetic. But again, recognizing three of something (or even being conditioned to react to three physical objects) does not mean recognizing three as such.

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  35. DavidM

    No David, the catch is this: Our brain work ligh differently therefore we have different sensations.

    Torley is pretty damn much going for that.

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  36. Eduardo,

    "I think my man, you have actually unwantedly agree to Authority Anon. Are you not saying that as intellectual groups people have followed the great metaphysical of the great minds in the past???"

    What Burtt describes is a change in the Western 'Weltanschauung', so it's not really a matter of modern scientism advocates following the authority of Descartes, Newton, etc. It's in the air we breathe and the water we drink, so to speak. The general modern conception of nature - and man's place in it - is now completely different than from the pre-Scientific Revolution period. It is the worldview itself that is the 'authority', if you like. (This is one of Dr. Feser's criticisms of intelligent design, that it unwittingly follows this mechanistic worldview, so this isn't just confined to atheists/materialists.) The worldview, apart from it being difficult to see your way out of - and I should know, since I am myself an atheist - without philosophy/metaphysics, is self-reinforcing in that its foundation in science has an easy appeal to scientific 'success' (i.e., results = truth) and it is often dismissive of philosophy and/or metaphysics (i.e., where are the results?), the very things that might provide a view from outside the system. As Dr. Feser often says, the metaphysics are 'read out of' the mathematical/physical reductions; therefore, on this view, only science can tell us about the nature of the universe.

    (and, responding to DNW above, yes, Burtt was very influential in the history and interpretation thereof of science)

    The 'Burtt Anon'

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  37. Photons of certain wavelengths are absorbed by the lemon's surface. The wavelengths that get absorbed depend on the molecular structure of the compound that makes up the lemon's surface. Photons that are not absorbed get reflected by the lemon. Those reflected photons hit our retinas, and the light input is converted into action potentials. These action potential are integrated in the brain, and the sensation of that thing we call "yellow" is produced. Do note that all matter is actually colorless; this includes all the photons (both absorbed and reflected), the surface of the lemon, the retina, the action potentials and the integrating neurons. So whence is color?

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  38. "So whence is color?" - Color is a quality of the material substance which is a lemon. Please look at a lemon and do note that the surface of the lemon is indeed colored.

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  39. If one had to define science in a single short sentence, how would one do it?

    Personally I'd say "Science is the systematic method of uncovering and describing how matter behaves."

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  40. Burtt Anon

    Just to see if I on the right track here... you were the anon that used the Standford link last time, when the other guy talked about mathematics and science didn't you???

    If not, gotta say I feel like you have the same tone...

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  41. "Color is a quality of the material substance which is a lemon. Please look at a lemon and do note that the surface of the lemon is indeed colored."

    I was merely highlighting the problem of qualia. But still, I wonder how non-materialism solves the qualia problem. Why do some wavelengths result in certain sensations? I am genuinely honest. And I'm not endorsing materialism here; I know that materialism still has some pretty glaring (and perhaps insoluble) issues.

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  42. Eduardo,

    "Just to see if I on the right track here... you were the anon that used the Standford link last time, when the other guy talked about mathematics and science didn't you???"

    No, I don't know what you're referring to (at least I don't think so - I haven't commented any time recently, nor am I a regular anonymous commenter).

    Burtt

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  43. Interesting, there is another fish just like you lurking XD then.

    Well I will let you carry on with your discussion, I am too green to have anything to add.

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  44. This comment has been removed by the author.

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  45. Anonymous:

    I think it's misleading to say that matter is actually colorless. All we can say is that the phenomenon of color depends critically on our eyes and brains, and that some things have the power to elicit this phenomenon in us and others don't.

    Edward M:

    I agree that lemons are visible in the sense that they have the capacity to be seen by us. But the active power they possess I would simply define as the power to reflect photons, and nothing more than that. If it means anything more than that, you end up imputing an indefinitely large number of powers to lemons, as there may be indefinitely many alien life-forms out there, all with very different-looking sensory organs that pick up photons of light.

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  46. Sorry, that should have been David M.

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  47. ingx24,

    I asked a similar question to yours in the comment thread to the post here (under the pseudonym 'rmac'): http://edwardfeser.blogspot.com/2012/06/sentient-plants.html

    Commenters Glenn and Sobieski gave what I found to be satisfactory answers. See if that helps.

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  48. Ian:

    If I'm understanding this correctly, the basic jist is that A-T still sees sensation and imagination as immaterial, but dependent on material organs in a way that pure intellectual activity is not. Am I understanding this properly?

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  49. ingx24,

    That is my understanding as well.

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  50. @Vincent Torley:

    "If it means anything more than that, you end up imputing an indefinitely large number of powers to lemons, as there may be indefinitely many alien life-forms out there, all with very different-looking sensory organs that pick up photons of light."

    I'm not sure that's true.

    We might be imputing lots of different properties to it if we said it was, in itself, all of the different colors that it might appear to anyone under the sun or elsewhere.

    But why couldn't we attribute to it one power that expresses itself differently, or has different effects, under different conditions and/or to different observers? And if we can, could not that power be something more than the power to reflect photons and include, for example, the power to cause certain qualia in certain experiences under certain conditions?

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  51. I wonder at the wisdom of trying to compare the qualia of two individuals as they look upon a lemon (standard lemon, white light).

    If we actually had a mechanism that could compare qualia then qualia would automatically be subject to a materialist scientific program. We would only have to calibrate the instrument that we had used to compare these qualia against some standard observer (to be kept under glass in Paris) and then we could evaluate all the "yellows" that different people saw and compare those results against observations of the brain.

    If the mind is immaterial, then comparison must take place immaterially. I haven't the slightest idea how that could happen (I'm open to the possibility, but my imagination fails).

    So reasoning from what we imagine is going on inside the head of the other is probably not sound. Or at least so it seems to me, as my private metaphysical framework forbids taking impossible things as logical premises.

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  52. Just to defend Alex the parrot a bit more: He didn't answer questions using the Clever Hans method (the researchers were well aware of Hans, and I'm not sure how it would have worked anyway, as Alex said his answers out loud instead of tapping his foot until he got body-language cues, and I doubt there's much difference in body language between people who hope for the answer "four" and people who hope for the answer "five".)

    To me, it seems like Alex had a decent grasp of some abstract concepts - apart from numbers up to six, colors and materials, he could answer questions about which object was bigger or smaller, and whether objects were similar or different.

    From Wikipedia: "Alex had a vocabulary of about 150 words, but was exceptional in that he appeared to have understanding of what he said. For example, when Alex was shown an object and was asked about its shape, color, or material, he could label it correctly. He could understand that a key was a key no matter what its size or color, and could figure out how the key was different from others. He asked what color he was, and learned 'grey' after being told the answer six times. (...) Preliminary research also seems to indicate that Alex could carry over the concept of four blue balls of wool on a tray to four notes from a piano."

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  53. Martin,

    Your argument assumes that having a concept is merely a discriminatory capacity. It's not. A concept is the sort of thing we can reason about; hence anyone employing a concept should be able to provide a rational justification for why one object falls under a concept while another object doesn't. Could Alex explain why an oval-shaped object shouldn't be called circular, for instance? No, because he was incapable of critical thinking.

    I wrote a blog piece on the alleged reasoning capacities of crows last year: http://www.uncommondescent.com/intelligent-design/are-crows-capable-of-reasoning-about-hidden-causal-agents-five-reasons-for-skepticism/

    Happy hunting.

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  54. Oh wait, that crow thiking thing, some guy asked this here before, but he never got a reply from anyone.

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  55. Hi Scott,

    You ask whether a lemon might not have a single power to cause certain qualia in different kinds of aliens under certain conditions. But if the sensory organs of these aliens are very different, having nothing in common except their responsiveness to light, then why would you impute the resulting qualia in various kinds of aliens to the operation of a single power on the lemon's part - unless that power merely involved reflecting photons of light?

    Another thing that puzzles me is that if we say lemons have a built-in power to cause qualia, then we're imputing psychic properties to lemons: we're saying that aside from having structural properties and powers to move other bodies, they also have these funny powers to cause phenomenal experiences. And that's bad news, because whereas you might be able to explain the structural properties and physical powers within the framework of a single unified model that could explain everything about lemonhood, there's no way you could come up with a model that would incorporate all these powers and the phenomenal powers as well. So you'd have to give up on the "unified model" approach, and say that all scientists can do is catalogue the various powers of lemons, without being able to come up with a common framework to explain them all. That's not science. That's bean-counting. It's a fate too depressing to even contemplate. Take away models, and you take away all the joy and beauty of science.

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  56. Vincent.

    Errr... weren't models exactly supposed to be representations of the parts we are studying???

    Or you mean Science's job is to Unify things?

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  57. Ok, I think I get why sensation and imagination are said to be "material" on A-T philosophy of nature now. It's not that sensations and mental images are themselves material, but that they are activities performed by material organs - that is, on A-T, matter has the ability to do things like sense and imagine in virtue of being in certain forms, and is not limited to only performing observable, "mechanical" activities like it is in modern philosophy.

    Am I understanding this correctly?

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  58. matter has the ability to do things like sense and imagine in virtue of being in certain forms

    Sorry, I should clarify: When I say "certain forms", I mean the forms of animals and/or their various organs.

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  59. Vincent,

    If joy and beauty are part of science-with-models, why is yellow not part of a lemon?

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  60. Re: Lemons and Qualia...

    It seems to me that the one constant in the myriad versions of qualia associated with the lemon is - the lemon.

    Whatever the lemon has, it has in itself. The fact that every individual has a different qualia experience doesn't change anything about what the lemon is.

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  61. If joy and beauty are part of science-with-models, why is yellow not part of a lemon?

    Poorly phrased; better this way:

    Take away models, and you take away all the joy and beauty of science.

    If joy and beauty are part of 'science-with-models', why is yellow not part of 'lemon'?

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  62. VT: "But the active power they possess I would simply define as the power to reflect [a certain spectrum of] photons, and nothing more than that." - So you're assuming that 'being yellow' or 'the yellowness of the lemon' has to be something 'more' than that? I would assume that that is just what the natural being (esse naturale) of yellow consists in.

    VT: "Another thing that puzzles me is that if we say lemons have a built-in power to cause qualia, then we're imputing psychic properties to lemons: we're saying that aside from having structural properties and powers to move other bodies, they also have these funny powers to cause phenomenal experiences." -- I'm confused. I thought we already agreed that lemons are visible (i.e., able to cause the experience of sight - although only when illuminated, of course - in something that is able to see). But what is the point of calling this a 'psychic property'??

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  63. @Vincent Torley:

    "But if the sensory organs of these aliens are very different, having nothing in common except their responsiveness to light, then why would you impute the resulting qualia in various kinds of aliens to the operation of a single power on the lemon's part - unless that power merely involved reflecting photons of light?"

    I see your point. Perhaps it's better to regard the photons themselves as having the power to affect sensory organs in ways that give rise to the experience of color-qualia.

    Either way, I think I'm inclined to agree with DavidM that the esse naturale of yellow may well consist in the power to reflect a certain spectrum of photons—whether or not we "read back" the qualia-generating powers of those photons (or of something even further downstream) into the lemon itself.

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  64. Vincent Torley: You ask whether a lemon might not have a single power to cause certain qualia in different kinds of aliens under certain conditions. But if the sensory organs of these aliens are very different, having nothing in common except their responsiveness to light

    ... then they aren't so "very" different after all. (Unless you mean they are different in that they do not react to visual qualities, but only to the quantitative aspects of light — like an unconscious camera — in which case they simply aren't relevant.) But of course the lemon's quality of colour is not the only thing that is applicable to my sensation. If the lemon looks different to me because I put on sunglasses, that obviously requires no extra powers in the lemon itself — any more than it requires extra textural powers to feel different when I touch it barehanded vs. touching while wearing gloves. But surely the texture of the lemon is something in the lemon itself!

    Another thing that puzzles me is that if we say lemons have a built-in power to cause qualia, then we're imputing psychic properties to lemons

    No, we're saying that it has qualitative properties. If we cannot include qualities in "the framework of a single unified model" because that model is "mathematical physics", then that's hardly surprising, for qualities are not quantities. I don't see how the fact that everything does not reduce to physics takes anything away from what physics genuinely is. It is simply an acknowledgement that God has "colour-coded" (as well as sound-coded, texture-coded, etc.) the material world, so that we can appreciate it both qualitatively and quantitatively.

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  65. Scott: I see your point. Perhaps it's better to regard the photons themselves as having the power to affect sensory organs in ways that give rise to the experience of color-qualia.

    In theory, we could suppose that matter generally lacks qualities, and that quantitative features cause (directly or indirectly) qualitative sensation in our minds; but to the Aristotelian that's unwarranted eliminativism. However, I think the case of vision is different enough from our other senses that we could raise the still-realist question of whether colour is in the objects seen or in the light. Some sensations, e.g. touch are direct, while others are mediated, e.g. sound — but you can put your ear directly on a vibrating object and hear it without needing the medium of air. Putting your eye directly on something, however, will not help you see it (it will probably block out the light and prevent your seeing any colours at all). Furthermore, we can create coloured light that is not reflected off some coloured object (such as the light you are presumably seeing off your computer screen at this moment — the letters, windows, buttons, etc. are not real coloured objects, but exist only as emitted light).

    Of course, Aquinas was hardly unaware that we can't see in the dark, etc. As I recall, he considers light to be necessary for seeing because it is required to activate the medium (e.g. air) to carry colour (much as your cell phone requires power to be able to transmit sound, I suppose). This has the advantage of making things actually be coloured, just the way we naturally think they are. Against this is the argument that it makes the physics more natural to think that is it the light that is coloured... however far that can be reasonably pressed.

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  66. ingx24:

    Treating internal mental images as "material" when they are clearly not observable in the brain doesn't make sense to me, and I'm not sure if that's a misunderstanding on my part or if the definition of "material" is that much different in A-T than it is in modern philosophy.

    I believe the highlighted part is correct. Recall that even material substances are not entirely material in the modern sense, in that they have a form and final causes.

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  67. Hi everyone,

    Thanks for your responses. I've been turning things over in my head, and I now think it's probably incorrect to say that lemons or any other material objects outside the human body have a built-in tendency to cause qualia. Objects outside the body - and this goes for vision as well as touch - activate sensory neurons (see http://en.wikipedia.org/wiki/Sensory_neuron ) which convert the stimuli into electrical information. This information then travels to the central nervous system and eventually reaches the brain. Within the brain, the information has to reach the neocortex before we experience the qualia that characterize phenomenal consciousness. If the flow of information is arrested at any point before reaching the neocortex, no qualia will be experienced. This has been confirmed experimentally. See the paper by Rose which I referred to above, as well as his online paper, "The Neurobehavioral Nature of Fishes" at http://www.nal.usda.gov/awic/pubs/Fishwelfare/Rose.pdf .

    Thus it is only when electrical signals reach the interconnected network within the neocortex that qualia occur. This is an event occurring within the human body, at some time after the external stimulus activates the sensory neurons. There is thus no need to impute qualia-causing properties to lemons; what we should say is that within the body of a sentient organism, the movement of one part can cause the organism to experience qualia.

    Thus instead of saying that God has "colour-coded" (as well as sound-coded, texture-coded, etc.) the material world, so that we can appreciate it both qualitatively and quantitatively, I would say that God has "colour-coded" the brain. I would certainly agree that the human body (including the brain) cannot be understood within the framework of any reductive theory. As for inanimate objects, they may well turn out to have higher-level properties that don't reduce to lower-level ones: even water has physical properties that can't be explained by the fact that it's H2O, I believe. But what I would say is that at each level we should look for a unified model that encompasses all the properties within a single explanatory framework. However, I doubt whether we'll ever have a satisfactory unified model for organisms, and certainly not sentient ones. They may be impossible for us to really grasp.

    Mr. Green argues that texture is surely a property of lemons. But texture can be understood as a property of surfaces (see http://en.wikipedia.org/wiki/Surface_texture ) and in that sense it reduces to shape. The qualitative feel of the surface is an event which occurs within the human body - or more accurately the brain.

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  68. Vincent...

    Isn't something awakward to just attribute neural patterns to qualia... We would be just experiencing ourselves, always... all the time.

    No need for an external world to begin with.

    I mean, there is something awkward with that system...

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  69. Vincent,

    This is the argument for which David Stove awarded the prize of The Worst Argument in the World. The argument runs:

    1. We only know things as far as they are related to us (they affect us, they interact with us, etc.)

    2. Therefore, we don't don't know things as they really are (as they are in themselves, etc.)

    The argument in its snappier form is "we have eyes, therefore we cannot see" (Olding). It's a curious coincidence you give it in exactly the context chosen by Olding (though you substitute eyes for nerves, neurons, neocortex etc.).

    To answer your argument straight, the fact that that perceiving a lemon is accompanied by certain physiological processes, or that if those processes are artificially distorted the accompanied qualia change, does nothing whatsoever to show or even suggest that it is not the lemon (and it's quality of being yellow in particular) that we are perceiving.

    Source: http://web.maths.unsw.edu.au/~jim/worst.html

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  70. Hi Jan,

    I'm certainly not arguing that we don't perceive lemons. I'm simply arguing that we don't need to impute peculiar qualia-producing tendencies to lemons in order to account for our perception of lemons. The fact that they excite our sensory neurons, which then relay electrical signals to the central nervous system and thence to the neocortex, is sufficient to account for that fact.

    How is our perception, then, a perception of a lemon? First, it was ultimately caused by a lemon, via a standard, "non-wayward" chain of causality, and second, it is a perception about that lemon, insofar as it contains information which points to the lemon in a reliable fashion.

    Eduardo,

    Thanks for your query. Let me just say that I'm not attributing neural patterns to qualia. Rather, I'm attributing qualia to neural patterns (or rather, movements): the latter cause the former, within the human body. As to your objection that this account of perception sounds solipsistic: the phenomenon of phantom pain (not to mention hallucinations) proves that qualia need not always have an external origin. But I would say that in a properly functioning human body, they typically do. (See my above remarks in reply to Jan.) It's just that in sensu stricto, the external cause of a qualia is a per accidens cause rather than a per se cause, owing to the time-lag effect and the (conceptual and actual) possibility of qualia occurring without an external stimulus.

    We could say (in a counterfactual sense) that if the lemon hadn't been there, I wouldn't have experienced its yellow and sour qualities. True, but that's not enough to make the lemon a per se cause of my perceptions, in sensu stricto. I could say that if my maternal grandfather and grandmother hadn't met on a train, I wouldn't be here now; and yet they are not the per se but the per accidens causes of my coming into existence, according to Aquinas.

    I'd still be happy to say that external objects are the proper (and ultimate) causes of our phenomenological perceptions; it's just that I'd reject the view that a proper cause has to be a per se cause.

    I hope that makes sense.

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  71. @Vincent Torley
    "Thus it is only when electrical signals reach the interconnected network within the neocortex that qualia occur."

    It seems to me that we don't have to rhetorically dissect a brain to get to this argument : qualia will also not occur if the lemon is not illuminated.

    So is a lemon in the dark still yellow?

    Is a lemon still yellow if the eyes beholding it and the brain it is attached to are not responsive to the yellow wavelengths of light?

    Is it still yellow if the observer speaks one of those languages that has no word for yellow, and regards it only as a particularly warm shade of green?

    Is the lemon still yellow even if it the lemon we are talking about in this context, which is not a real lemon, but a rhetorical one for the purposes of a conversation among people who will never be in the same room with the same lemon?

    I think the answer to all of these questions must be yes.

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  72. Vincent.

    Alright so you are saying that there must be a medium YOU can perceive the LEMON, but I seriously think nobody here disagrees, rather it was you who leaped towards the lemon's power being psychic in nature, directly related to human brain pattern.

    Don't you agree that you created the knot?

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  73. Vincent,

    Will that whole chain of events still induce the qualia of 'seeing the lemon' if the lemon doesn't exist to be seen?

    If not, then the lemon is the 'first cause' of that chain.

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  74. "So is a lemon in the dark still yellow?"

    I think the physicalist would respond that it isn't yellow in the dark, because it was never yellow in the first place.

    Perhaps the Aristotelian could answer by saying that it is not yellow in the dark, but it has the potential to be yellow, a potency which is actualized by photons. But then this raises the question: Does the event of photons hitting the surface of the lemon involve genuine change? IIRC, the color of an object (that we see), is actually complementary to the color of the light that gets absorbed by the surface. I guess both the absorption and deflection of the photons can count as genuine changes.

    “Will that whole chain of events still induce the qualia of 'seeing the lemon' if the lemon doesn't exist to be seen?

    If not, then the lemon is the 'first cause' of that chain.”

    If photons did not exist, would the chain of events exist? If there was no big bang, would photons exist?

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  75. If photons did not exist, would the chain of events exist? If there was no big bang, would photons exist?

    All of those things will cause the chain to cease - yes - but they cause many other chains to cease as well.

    If we have no eyes, or if there's no light, then we can't see the lemon, but we also cannot see the dog, the cat, the road, etc.

    If we don't exist, then we can't see or do anything at all.

    My question was specifically about the qualia "seeing the lemon" though. The only thing that will stop that and only that qualia (while still allowing all other sight-related qualia), is the absence of the lemon itself.

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  76. For the record, ladies and germs, the singular of qualia is quale. ;-)

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  77. @Daniel Smith:

    "My question was specifically about the [quale] 'seeing the lemon' though."

    I wouldn't call that a quale. A lemon, as seen, is a complex of characters including a (range of) color(s), each one of which is a quale. I think you're talking about an overall experience rather than of the individual characters or properties that are its "objects."

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  78. Scott: For the record, ladies and germs, the singular of qualia is quale.

    Thank you!

    I wouldn't call that a quale.

    I didn't! I called it "qualia" which, it turns out, is plural!

    ;)

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  79. @Daniel Smith:

    "I didn't! I called it 'qualia' which, it turns out, is plural!"

    Heh, I actually thought of that before posting. But (at the risk of sounding pedantic here) I think it's still not what you meant.

    "Seeing a lemon" is an experience, not a complex of qualia. Those qualia (experienced qualities/characters) may be the object of such an experience, but they're not the experience itself. You and I could experience the same qualia in looking at the lemon, but we'd still be having two different experiences.

    You could, however, take your phrase "the qualia of seeing a lemon" (my emphasis) to mean the qualia that one experiences in seeing a lemon!

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  80. @Anonymous,
    "But then this raises the question: Does the event of photons hitting the surface of the lemon involve genuine change?"

    The ontological status of bosons kind of makes my brain hurt anyway. It is perfectly legitimate to treat all photons as absorbed and then new photons emitted using the absorbed energy. It is perfectly legitimate to treat the photon as not existing at all, except insofar as it represents an interaction between an electron in the lemon and an electron in the eye.

    It sort of depends on what you think light is in the first place, and which model suits your purposes.

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  81. Scott: You could, however, take your phrase "the qualia of seeing a lemon" (my emphasis) to mean the qualia that one experiences in seeing a lemon!

    Yeah, let's go with that!

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  82. @Daniel Smith:

    "Yeah, let's go with that!"

    Right there with you. Consider it done.

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  83. -- OFF TOPIC --

    I'm not sure how else to get in touch with the Feser Fan Club other than to hijack a recent comment thread. A. C. Grayling's The God Argument: The Case against Religion and for Humanism popped up on my radar today. This looks interesting and I'm hoping he takes Aquinas' Five Ways seriously and correctly (that is, no straw men). I hope Dr Feser has an opportunity to read and publicly review it.

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  84. Kiel, does he really discuss the Five Ways in that book? I just checked the index via Amazon's preview, and it seems Aquinas is mentioned once... on page 141. And "Five Ways" does not seem to appear in the index.

    From the table of contents, it seems like he's going to bash ID, go after the wager argument, the teleological argument, and the ontological argument.

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  85. I'm really not sure. Going by page 268 of the index, he spends 41 (!!!) pages on "theistic arguments". I probably should not have said "the Five Ways" when I really meant the First Way.

    Not so hopeful anymore. I will still probably give it a read because he's one of the more prominent atheistic writers and I'd expect his thought to be representative of what an atheistic philosopher might think. I'd also like to hear a positive case for atheism and more about their accounts of humanism with respect to morality.

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  86. Why do I suddenly want a shot of tequila?

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  87. Because you've run out of scotch?

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  88. When some people are asked how anything came to be they answer that it comes from God. Others who, for whatever reason are quite rightly not convinced of the presumed answers of conventional "creator"-God religion answer, I do not know. Both types of people are being very honest within the limits of their understanding.

    How can they both be telling the truth? Well, because they are both telling you the same thing in different ways. Because, nobody - not mom or dad, or grandmother or grandfather, or big sister, or big brother, or teachers, or doctors, or priests, or philosophers, or theologians, or any people who are playing, not even a president, not even a King or Queen, not even people who love each other - nobody knows what a even a single thing IS.
    It is a great and more-tan-wonderful Mystery to everyone that anything is, or that we are. And whether somebody says, I dont know how anything came to be, or God made everything, they are simply pointing to the feeling of the Mystery - of how everything merely is, but nobody knows what it really iS, or how it came to be.

    As long as you go on feeling this Mystery, you feel free and full and happy - and you feel and act free and full and happy to others.

    If you remember to feel the Mystery all the time you will have lots of amazing more-than-wonderful experiences while awake. And, if you remember the Mystery even when you are going to sleep, then you will go to sleep all happy in the Mystery. and you will always wake up in the Mystery, too. And all your dreams will be about the Mystery, too.

    Remembering the Mystery is a way of being everything you always already are. When you feel the Mystery real strong, you can even breathe the Mystery. When people feel the Mystery real strong and breathe it, they say things like, God is Spirit, because Spirit is just a name for what people feel about their breath. They are just wondering beyond wondering - how the Mystery even goes all through them, and doesnt have any shape or face or up or down or inside or outside. The Mystery is good feeling, full of light and happiness and love - isn't It?

    If you are really sensitive to the intrinsic fullness of the Mystery you will discover that you ARE the Mystery! Yes! And you dont even know what you ARE, either. Yes!, There IS ONLY the Mystery! And you yourself - in your Real Heart, and up and down and in and out - ARE the Mystery. It IS All ONE FEELING!

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  89. Steve, if you're getting a shot, can you get me one too please?

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  90. Graylng... He debated Craig once, when he went on that tour in England.

    This is a bet... But I doubt he will take anything seriously, just think about the subtitle.... He is equating religion to belief in God, now this works here in the West where most religions are theistic, but it is not true that religion is the same as believing in God.

    The humanist movement is also political in nature, and the humanism Grayling defends is Secular Humanism, I don't think he will deal them in a precise philosophical way, but will deal with them to cause the best political commotion....

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  91. reighley,

    A lemon in the dark is just as yellow as a lemon in the light. Both have a built-in tendency to reflect photons of a certain wavelength, in a way which sentient human beings perceive as "yellow." If the yellowness of a lemon means having such a tendency, then lemons in the dark are yellow.

    By the way, I can't agree with your suggestion that maybe photons don't exist after all. If a photon is nothing, then what happens when an electron meets a positron and the two destroy each other, creating a photon in the process? If you're right then this would be a case of genuine annihilation.

    Daniel Smith,

    I'd agree with your claim that the lemon is the 'first cause' of the causal chain that occurs when I see a yellow lemon. I'd also agree that when I see an object called a lemon, the lemon is the per se efficient cause of my perceiving an object as such. However, I'd also maintain that the lemon, per se, doesn't explain the fact that I perceive it as phenomenologically yellow: that is, it doesn't explain the quale as such (thanks, Scott). The per se cause of my phenomenological experience is the excitation of the relevant neurons in my brain, of which the lemon is only the per accidens cause.

    Eduardo,

    I'm genuinely sorry if my terminology created confusion, in my earlier posts. My own thinking on the subject was still evolving, and is, even now.

    Kiel,

    I blogged on A. C. Grayling's arguments against the existence of God here (there's also a plug for Ed's Aquinas in one of my posts):

    http://www.uncommondescent.com/intelligent-design/is-the-notion-of-god-logically-contradictory/

    http://www.uncommondescent.com/intelligent-design/of-pegasus-and-pangloss-two-recurring-fallacies-of-skeptics/

    http://www.uncommondescent.com/intelligent-design/is-this-the-dumbest-ever-refutation-of-the-fine-tuning-argument/

    In short, I wouldn't get my hopes up, if I were you.

    Hope that helps.





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  92. If this discussion involves the experience of some quale, then instead of a lemon, should the example not be a potatoe?

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  93. @James:

    "If this discussion involves the experience of some quale, then instead of a lemon, should the example not be a potatoe?"

    Heh. It's pronounced "qually," not "quail," but the joke works in print.

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  94. Vincent wrote: "...it is only when electrical signals reach the interconnected network within the neocortex that qualia [i.e., the esse intentionale of, e.g., yellow] occur. This is an event occurring within the human body, at some time after the external stimulus activates the sensory neurons. There is thus no need to impute qualia-causing properties to lemons..." -- Huh? Why not? (Or have you already retracted this claim?)

    "...what we should say is that within the body of a sentient organism, the movement of one part can cause the organism to experience qualia." -- Sure, but the movement of that part is still caused by... none other than... the natural yellowness of the lemon. The fact that it can also be caused by other causes doesn't change that fact.

    "I would say that God has "colour-coded" the brain." -- Weird. I would just say that the brain is necessary for perceiving color (the color of things like lemons).

    "The fact that [lemons] excite our sensory neurons, which then relay electrical signals to the central nervous system and thence to the neocortex, is sufficient to account for that fact [that we perceive them]." -- But you admit you have no reductive account of this, so why not just accept that the fact that lemons do this is dependent on the fact that the purpose of our sense of sight (including all that neocortical apparatus) is to perceive colored objects?

    "How is our perception, then, a perception of a lemon? First, it was ultimately caused by a lemon, via a standard, "non-wayward" chain of causality," -- That does NOT make it a perception of a lemon, surely? -- "and second, it is a perception about that lemon, insofar as it contains information which points to the lemon in a reliable fashion." -- But it seems that on your account it does not do this. On your account our perception of color seems to point rather to something about the powers of our neocortex to generate qualitative experience, precisely NOT to information that is genuinely about the lemon.

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  95. @Scott: Well done in divining the meaning of that potato comment - I had no idea...

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  96. Mr. Green wrote: "we could raise the still-realist question of whether colour is in the objects seen or in the light" -- I believe that according to Aquinas the natural being of color is in the object, while the intentional being of color is in the *illuminated air* (as well as in the activated sense power), so not in light per se, but in the illuminated medium.

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  97. Vincent

    Don't worry about it man, I was just pointing to what I think was the problem.

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  98. Nice review of TLS in the German catholic magazine Theologisches by German Philosopher Walter Hoeres. He has a lot of interesting things to say and praises the book apart from a minor criticism which he points out does not diminish the importance of this great work:)

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  99. Nice review of TLS in the German catholic magazine Theologisches by German Philosopher Walter Hoeres. He has a lot of interesting things to say and praises the book apart from a minor criticism which he points out does not diminish the importance of this great work:) Greetings from Germany, Robert.

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  100. Given the previous works and public presentations of A. C. Grayling, I find unreasonable to expect anything other than the typical New Atheist rage and shallowness.

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  101. Vincent: I'd also maintain that the lemon, per se, doesn't explain the fact that I perceive it as phenomenologically yellow: that is, it doesn't explain the quale as such (thanks, Scott). The per se cause of my phenomenological experience is the excitation of the relevant neurons in my brain, of which the lemon is only the per accidens cause.

    Well, I'd argue that not every yellow is the same and the reason you see that particular yellow, (and not some other yellow or some other color) is still all because of the lemon.

    IOW, the color of the lemon, no matter how you perceive it, is different from the other colors you perceive because of one thing - the lemon.

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  102. Hi Daniel Smith,

    I'd certainly agree with you that the lemon itself is the cause of the variations in color which I perceive on the surface of the lemon - for example, mites on the skin can cause grey spots to appear on the lemon. I'd also agree that the reason why lemons have the distinctive shade of yellow that they do is rooted in the lemon itself. However, the fact that I perceive it (phenomenologically) as a shade at all rather than merely sensing it (as most animals do) without any accompanying phenomenological perception is something which is explained not by the lemon as such, but by the properties of my brain (especially the neocortex) and nervous system.

    DavidM

    Sorry for my change of mind, but as I think I mentioned earlier, I no longer see any need to impute qualia-causing properties to lemons. You argue that movements of neurons in my body are ultimately caused by the lemon itself. True, but the fact that I perceive these movements phenomenologically, as a color, is explained by the properties of my neocortex. As far as the neocortex is concerned, so long as the right electrical signals arrive from the right areas of the visual cortex (especially V1), color perception will occur. The earlier fact that photons emitted by the lemon stimulated my sensory neurons, causing electrical signals to travel to my brain, doesn't explain my phenomenological experience of color any more than my grandparents' meeting explains my coming to be.

    You object that on my account, the perception of yellow wouldn't point to the lemon as such. But if changes in the colors I perceive track changes in the lemon - e.g. if I perceive its skin as grey instead of yellow after it gets infested with mites - then it seems to me that my perception does point to the lemon, after all.

    As for the purpose of our sense of sight, I'd say that it's simply to see objects (such as lemons) that reflect photons in the frequency range corresponding to visible light.

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  103. VT: "The earlier fact that photons emitted by the lemon stimulated my sensory neurons, causing electrical signals to travel to my brain, doesn't explain my phenomenological experience of color any more than my grandparents' meeting explains my coming to be." -- Are you sure about that? There is surely no per se functional connection between your grandparents meeting and your coming to be. But surely there is a per se functional connection between the sensory stimulation of your neurons (and then brain) by the photons reflected by objects such as lemons and your phenomenological (visual) experience of such objects? Why do you deny this?

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  104. "As for the purpose of our sense of sight, I'd say that it's simply to see objects (such as lemons) that reflect photons in the frequency range corresponding to visible light." -- Naturally, then, it is the lemon's own yellowness that one sees, if the purpose of seeing is to see objects such as lemons. But you want to maintain that to 'see' is just to 'track changes in'? That sounds very implausible. There obviously has to be more to seeing than that. If the lemon never turns gray (or any other color), surely I'm not *seeing* it any the less.

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  105. "But if changes in the colors I perceive track changes in the lemon - e.g. if I perceive its skin as grey instead of yellow after it gets infested with mites - then it seems to me that my perception does point to the lemon, after all." -- Not to belabor an obvious point, but if I look at a real-time spectrograph of a lemon I can track changes in the lemon - doesn't mean I'm *seeing* the lemon.

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  106. If this is any different from the ancient chestnut about whether a tree falling in a forest with nobody there can be said to make a sounds --- well, I can't see it. Hard to believe that one is still sending people spinning into confusion in this day and age.

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  107. @One of the many anonymous posters hereabouts (who I wish would adopt screen names so that we could tell them apart):

    "If this is any different from the ancient chestnut about whether a tree falling in a forest with nobody there can be said to make a sounds --- well, I can't see it."

    I think it is. The discussion here is about whether the causal power to produce a certain quale (or range of qualia) is best said to reside in the apparently colored object or somewhere else (photons, eye, brain, neurons, etc.). It's not about whether a lemon has a color when no one is looking at it.

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  108. Vincent: However, the fact that I perceive it (phenomenologically) as a shade at all rather than merely sensing it (as most animals do) without any accompanying phenomenological perception is something which is explained not by the lemon as such, but by the properties of my brain (especially the neocortex) and nervous system.

    Yes, that explains the fact that you have qualia (full stop) and other animals don't. But it doesn't explain why you have a different quale for the color of the lemon than you do for all other objects. That specific quale is due to the lemon. If it wasn't, how would you account for the differences in qualia you experience? After all, you're the same "you" in all of it.

    As an example, take the quale you experience when you listen to your favorite piece of music. Your argument is that that music has no power to induce that quale but it is, rather, the auditory nerves, sound waves, etc. If that's the case though, then why is it only that particular piece of music that can evoke that reaction? It's got to be more than just sound waves and nerve impulses. There has to be something about the music itself.

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  109. @Daniel Smith:

    "That specific quale is due to the lemon. If it wasn't, how would you account for the differences in qualia you experience?"

    I don't think there's any dispute here about whether the occurrence/experience of this or that specific quale is in some way due to the lemon. The dispute is about whether the lemon has the causal power to produce that quale directly, or whether it has only the causal power to do something else that in turn causes that quale. Is the yellow "in" the lemon, or does the lemon just have the ability to reflect photons that themselves cause the experience of (this or that precise shade of) "yellow"?

    That's my understanding of Vincent Torley's point, anyway. If I'm wrong, I'm happy to be corrected.

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  110. Prof. Feser, a question. I believe that P.Z. Myers is quoting you in this post, but I'm not certain. http://freethoughtblogs.com/pharyngula/2013/02/26/i-can-defend-both-lawrence-krauss-and-philosophy/

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  111. @Richard:

    "Prof. Feser, a question. I believe that P.Z. Myers is quoting you in this post, but I'm not certain. http://freethoughtblogs.com/pharyngula/2013/02/26/i-can-defend-both-lawrence-krauss-and-philosophy/"

    Where and why do you think Myers is quoting Feser?

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  112. This quote right here sounds familiar. "Because scientists have a rather poor track record when it comes to doing philosophy.

    Sam Harris’s attempt to provide a scientific basis for morality springs to mind, where he poo poos metaethics only to tread squarely in a metaethical dilemma. Or Richard Dawkins and his dismissal of religion as a false belief system, meanwhile dismissing the rather significant psychological and cultural functional roles it has played throughout human history, and may still play today.

    Or Krauss, who without a hint of irony, suggests that good philosophers are really just bad scientists, when in fact he’s a good scientist doing philosophy badly. His definition of “nothing” comes not from within science, but is a grope in the dark for a definition that conforms with his particular theoretical predilections. That’s not how one defines things in polite (philosophical) circles, as David Albert pointed out."

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  113. @Richard:

    "This quote right here sounds familiar."

    Thanks for clarifying. I don't recognize the quote as Feser's, though, and Google doesn't turn up anything helpful.

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  114. However, the fact that I perceive it (phenomenologically) as a shade at all rather than merely sensing it (as most animals do) without any accompanying phenomenological perception is something which is explained not by the lemon as such, but by the properties of my brain (especially the neocortex) and nervous system.

    Are you using "perceive phenomenologically" as an equivalent for qualia? If so, on what basis can you reduce it down to neurophysiology? After all qualia are first person subjective experiences, while science operates from a third person, neutral position. Science, therefore, is inherently limited in its access to qualia. Of course, that doesn't mean that there are not necessary physical events that precede qualia, but that does not mean that we can reduce qualia to those events, nor can I see any way in which science could do so.

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  115. Anon: "If this is any different from the ancient chestnut about whether a tree falling in a forest with nobody there can be said to make a sounds --- well, I can't see it."

    Scott: "I think it is. The discussion here is about whether the causal power to produce a certain quale (or range of qualia) is best said to reside in the apparently colored object or somewhere else (photons, eye, brain, neurons, etc.). It's not about whether a lemon has a color when no one is looking at it."

    Me: I think I agree with Anon on this. Vincent seems to want to say that the *real* color *is* just the phenomenal experience of a quale, so there is no yellowness when no one is looking at something yellow (i.e., the yellowness of the lemon only exists in the mind of the observer - so no observer, no yellowness).

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  116. @DavidM:

    "Vincent seems to want to say that the *real* color *is* just the phenomenal experience of a quale, so there is no yellowness when no one is looking at something yellow (i.e., the yellowness of the lemon only exists in the mind of the observer - so no observer, no yellowness)."

    I took him to be saying in effect that the yellowness isn't "in" the lemon at all, whether anyone's looking at it or not. But I see your point and you may be right.

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  117. A little off topic. I am looking for a book that illustrates and contrast the "dialogue" between Plato and Aristotle and their corresponding works specifically in the area of metaphysics (although if it includes, ethics, politics, epistemology etc it would be just fine).

    I've been thinking a lot about these two nice fellas recently and wanted to see the influence one had on the other and how ideas were developed and contrasted between the two. I know Aristotle attempted to refute some of Plato's ideas but he nonetheless used a lot of them in his own works.

    Does anyone have any books to recommend?

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  118. Way off-topic: go to Feser's main page and click of "Lloyd Gerson" in his list of recommended philosophers. Gerson has written quite a bit about Aristotle the Platonist.

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  119. Scott: Is the yellow "in" the lemon, or does the lemon just have the ability to reflect photons that themselves cause the experience of (this or that precise shade of) "yellow"?

    I think both are true. The yellow is "in" the lemon in the sense that the lemon has the ability to reflect photons that in turn cause the experience of that precise shade of yellow.

    The beginning of the causal chain is the lemon though, not the photons.

    Lets think about the photons for a minute, if those same photons were to bounce off something else, would they still produce 'lemon yellow' quale? If not, then the photons are not the cause of 'lemon yellow' quale.

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  120. Somebody might have made this point already (I haven't looked through the comments), but there's a fundamental distinction between the problem of the origin of life and the origin of consciousness, looked at from the modern (and possibly incorrect) viewpoint. In the case of consciousness, as Chalmers and others point out, the problem is that we can't even in principle imagine how a purely materialistic explanation could work. Or at any rate even some very smart and well-informed atheists (like Chalmers) agree that this is the case at present.

    In the case of the origin of life, the situation is different. The very simplest organisms --bacteria--can be treated as immensely complex machines made up of smaller machines. The problem is how such a thing could have appeared. You couldn't go from simple chemicals to a functioning cell in one jump--here the standard creationist probability argument is actually valid. The Darwinian answer is to claim that there must have been much simpler forms of life (the current favorite is a self-replicating RNA molecule) that might conceivably originated via the usual laws of chemistry and physics and then, once reproduction is possible, the Darwinian process of random variation and natural selection could kick in and then lead to more complex organisms.

    The problem with the origin of life isn't necessarily (note that I am hedging) a fundamental philosophical problem like the origin of consciousness from mere matter. It really is just a question of probabilities, or one could plausibly argue this. There are various hypotheses about how it could have happened (like the RNA world), but none of them rise to the level of being a scientific theory because there's not enough evidence to support any of them that strongly. (Unlike the theory of evolution itself.) So one could argue that maybe there is no plausible way of bridging the gap between non-life and the very simplest possible life forms, but that's an empirical and yes, probabilistic question, one that in theory could be answered yes or no as we learn more. I think that because of philosophical bias it would take modern day scientists a long time before they would come to admit that life couldn't come into existence through the known laws of chemistry and physics, but from my perspective that's as it should be. If another century goes by (or maybe less) and we still don't have any good evidence that life could have arisen naturalistically, then it will be time for a paradigm shift of gigantic proportions. My timeline is somewhat arbitrary, but anyway I don't think we know enough yet to rule out a naturalistic origin with any degree of confidence. Of course the naturalists should admit (but frequently don't) that we also don't know enough to say that's how it happened.

    Donald

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