Marmodoro on PSR and PC

Philosopher Anna Marmodoro is an important contributor to the current debate within metaphysics over powers and dispositions, and editor of the recommended The Metaphysics of Powers.  Recently, at Notre Dame Philosophical Reviews, she reviewed Rafael Hüntelmann and Johannes Hattler’s anthology New Scholasticism Meets Analytic Philosophy, in which my paper “The Scholastic Principle of Causality and the Rationalist Principle of Sufficient Reason” appears.  What follows is a response to her remarks about the paper.

My paper is essentially a set of excerpts from chapter 2 of Scholastic Metaphysics.  The principle of causality (PC), in what I take to be its core formulation, says that a potency can be actualized only by some already actual cause.  (In the paper, and at greater length in the book, I discuss how other formulations follow from this one.)  Marmodoro focuses on a section of the paper in which I discuss how a Scholastic might (as some Neo-Scholastic writers did) argue for PC on the basis of the principle of sufficient reason (PSR).  Marmodoro quotes a passage from the paper where I summarize this sort of argument as follows:

[I]f PC were false — if the actualization of a potency, the existence of a contingent thing, or something’s changing or coming into being could lack a cause — then these phenomena would not be intelligible, would lack a sufficient reason or adequate explanation. Hence if PSR is true, PC must be true.

She then comments:

Let us pause to examine the inference from PSR to PC. Is it a valid one? PSR is about what makes the world intelligible to us. It involves reasons we give in our explanations of how things are, or how they happen. But the PC is about causes, not reasons. The two sets are not co-extensive. What makes a state of affairs intelligible may be other than its causes. To show that it has to be limited to its causes would require further argument. It would be interesting to hear more from Feser about how the Scholastics could respond to this critique.  

Prof. Marmodoro is in no way polemical and her questions are reasonable ones.  However, they also seem to me somewhat odd ones given that, contrary to the impression that she (no doubt inadvertently) conveys, I do address these issues in the paper!  The lines from me that she quoted come at the very beginning of the section on PC and PSR, and they merely introduce the topic.  They are followed by eight pages of discussion, and there is also about a page and a half of additional material, earlier in the paper and before the section she focuses on, where I discuss the differences between PC and PSR.  The lines Prof. Marmodoro quotes from me need to be read in light of all of this material.

One problem with Marmodoro’s remarks is that she seems to be attributing to me things I not only do not say but (as is clear from the larger context) explicitly deny.  She says that “the PC is about causes, not reasons. The two sets are not co-extensive. What makes a state of affairs intelligible may be other than its causes.”  But I and other Scholastic writers would agree with this.  I explicitly distinguish PC and PSR in just the way she does, and I explicitly say in the article that “all causes are reasons in the sense of making the effect intelligible, but not all reasons are causes” (p. 21, emphasis added).  Hence when Prof. Marmodoro goes on to say that “to show that [what makes a state of affairs intelligible] has to be limited to its causes would require further argument,” she is certainly correct, but I never said (and would not say) in the first place that what makes a state of affairs intelligible has to be limited to its causes.  That is simply not what is at issue among Scholastic writers who would derive PC from PSR.

Thus when Marmodoro later cites these closing lines of my paper:

All rational inquiry, and scientific inquiry in particular, presupposes PSR. But PSR entails PC. Therefore PC cannot coherently be denied in the name of science. It must instead be regarded as part of the metaphysical framework within which all scientific results must be interpreted.

and comments that “the validity of the conclusion however depends on the entailment already questioned,” she is mistaken, because in fact I never asserted the entailment she attributes to me, and indeed would deny it.

It seems to me that what has happened here is that Prof. Marmodoro, reading in isolation the lines from my paper she initially quoted, wrongly supposes that when I say that “if the actualization of a potency, the existence of a contingent thing, or something’s changing or coming into being could lack a cause… then these phenomena would not be intelligible,” I must be conflating “being intelligible” with “having a cause” (even though I explicitly reject such a conflation elsewhere in the paper).  But in fact the idea is rather this: A thing could be intelligible in itself rather than by virtue of having a cause -- for example, if it is purely actual rather than a mixture of actuality and potentiality, or if it is necessary rather than contingent.  But a potency that is actualized is not purely actual, a contingent thing is not necessary, etc.  Hence their source of intelligibility cannot come from their own natures but must lie in something outside them.  So in the lines Marmodoro quotes from me, the claim is not that what lacks a cause is not intelligible, but rather that what lacks either a source of intelligibility within itself or a cause is not intelligible.

Another potential problem with Prof. Marmodoro’s discussion is that it might give some readers the impression that I move, hastily and without argument, from considerations about “what makes the world intelligible to us” to a claim about what it is like in itself.  And of course, an objection sometimes made against Leibnizian rationalist applications of PSR is that such a move is fallacious.  PSR’s demand that things be intelligible to us is (so the objection goes) not something we have reason to suppose the world actually can meet.  Even if we couldn’t help but seek for explanations, it wouldn’t follow (the critic says) that they are really there.

But this is another issue I explicitly address in the paper.  I discuss the ways in which the Scholastic understanding and application of PSR differs from the Leibnizian rationalist understanding and application of it.  I note that PSR can be formulated without making reference to “intelligibility,” citing as an example Maritain’s formulation of PSR as the principle that whatever is, has that whereby it is.  I also note that there is, in any event, a conceptual route from claims about “what makes the world intelligible to us” to claims about what it is like in itself provided by the Scholastic principle of the convertibility of the transcendentals.  In particular, being and truth are on this view convertible with one another, insofar as they are the same thing considered from different points of view.  Being is reality as it is in itself, whereas truth is reality as it is considered by the intellect -- that is to say, it is reality qua intelligible.  If the doctrine of the transcendentals is correct, then, every kind of being is in the relevant sense true, in which case every being is intelligible, which is just what PSR says.  By the same token, everything that is intelligible is a kind of being.  Hence there isn’t the gap between reality’s intelligibility to a mind and what reality is like in itself that the critic of rationalist versions of PSR supposes there to be.

Obviously all of that raises various questions, but the point is that Prof. Marmodoro does not actually address the nearly ten pages worth of argument and exposition I put forward just on the topic of the relationship between PSR and PC (let alone the many other pages devoted to other questions about PC).  The one argument she does raise questions about (very politely, it must be acknowledged) is one that I not only did not give, but would reject!

Anyway, interested readers can read the article themselves, or read the longer discussion in chapter 2 of Scholastic Metaphysics from which it was excerpted.  And, again, I also commend to them Prof. Marmodoro’s fine anthology.