At first blush, Frege’s subject matter – the nature of propositions, their truth values, and logic as the science concerned with the study of these – couldn’t be further removed from political philosophy. But Frege was something of a Platonist, and as Plato knew well, metaphysics has political implications, not least when it is not directly concerned with politics at all. For there can be no sound political order that does not recognize something non-political existing beyond it, by reference to which it can be judged.
In “The Thought,” Frege reminds us that truth and the laws of logic are timeless and discovered rather than made – that, though they are grasped by time-bound human minds and conveyed through contingent human languages, they are independent of both. Lacking an essential connection to any particular human mind, they constitute neutral territory on which all minds can meet. The lesson is basic, but depressingly needed at a time when it seems there is almost nothing that is not becoming politicized, and where ideas are evaluated in terms of the motives, party affiliation, race, sex, or other irrelevant circumstances of the person presenting them, rather than by reference to disinterested criteria of truth and logical argumentation.
Frege’s essay is very rich, and there are well-known secondary themes in it that I will pass over for present purposes, such as Frege’s anticipation of what is now called the “redundancy theory” of truth, and his treatment of indexical expressions. What I want to focus on is the main theme, which is the objectivity of truth and logic.
First let’s get clear on what Frege means by a “thought.” He characterizes it as the “sense” of a sentence, and contemporary philosophers and logicians tend to prefer the word “proposition.” To take some stock examples, consider the English sentence “Snow is white” and the German sentence “Schnee ist weiss.” Being in different languages, they are different sentences, but they convey the very same proposition – namely the proposition that snow is white.
A proposition is therefore not to be identified with a sentence or indeed with any other set of physical marks or sounds, linguistic or otherwise. For not only can the same proposition be conveyed through different sentences, but it would remain either true or false even if there were no sentences to convey it through. For example, the proposition that snow is white was true before English, German, or any other language existed, and it would remain true even if all languages went out of existence tomorrow. Indeed, even if there were no material world at all, there would still be true propositions, such as the proposition that there is no material world. Logical relationships between propositions would still hold as well. For example, the proposition that all men are mortal and the proposition that Socrates is a man would entail the further proposition that Socrates is mortal whether or not Socrates, mortal things, or any other material thing existed.
Again, Frege refers to propositions as “thoughts.” Consider the way that, if an English speaker uttered “Snow is white” and a German speaker uttered “Schnee ist weiss,” we might say that the two speakers had the same thought or were thinking the same thing. What Frege is talking about, then, is not a thought in the sense of a particular psychological episode in the history of some individual mind – which is unique to the individual and thus cannot be shared by different minds – but rather the content that is grasped in the episode, which can be shared. It is because of the psychological connotations of the word “thought” that many prefer the term “proposition,” and I’ll follow that usage here.
So, propositions, their truth values, and their logical interrelationships stand apart from human minds and language, and even apart from matter. All the same, it is through the medium of language that we “grasp” them, as Frege puts it. He writes: “The thought, in itself immaterial, clothes itself in the material garment of a sentence and thereby becomes comprehensible to us. We say a sentence expresses a thought” (p. 292). Because sentences function as the means by which propositions are grasped, and because we grasp them in particular psychological episodes that may have various contingent causes, people sometimes fall into the trap of supposing that truth, falsity, and logic are artifacts of human psychology or language. Frege is keen to emphasize the fallaciousness of this inference.
Psychology and language
Psychology and logic are like apples and oranges. When I reason from the propositions that all men are mortal and Socrates is a man to the conclusion that Socrates is mortal, there may be any number of psychological factors that bring about that episode of thinking. Maybe someone put drugs in my coffee and that, for some reason, triggered the episode. Maybe I have a deep-seated hatred of Socrates and secretly delight in the thought of his mortality. Or maybe it has something to do with the way my psychology was molded by natural selection, or by capitalist economic institutions, or by the phallocentric heteronormative patriarchal hegemony, or whatever. None of that is in any way relevant to whether the inference is a good one. The conclusion does indeed follow logically from the premises, and that is that. As Frege emphasizes, laws of psychology (if there are any) are one thing, and the laws of logic another.
Similarly, a sentence may have various connotations, and the uttering of it or entertaining of it in one’s mind may be associated with various moods, feelings, mental images, and so on. None of that is at all relevant to the truth or falsity of the proposition expressed by the sentence, or to its logical relations to other propositions.
A written or spoken sentence is also a material entity, embodied in ink marks, sound waves, light patterns on a computer screen, or the like. We can see and hear these. But you cannot see, hear, or otherwise perceive the proposition expressed by the sentence, nor can you literally see or hear the truth or falsity of a proposition (even if you can see or hear things that lead you to judge it to be true or false) or the validity of an inference like the one about Socrates. Truth, falsity, validity, consistency, and other logical properties and relationships are not material properties and relationships.
So, again, human psychological states and processes and language are merely the vehicles through which propositions and their logical relationships are conveyed to us. The latter cannot be reduced to the former. The supposition that logical relationships are reducible to psychological ones is often called psychologism, and Frege’s essay is a classic attack on this error.
The three realms
Frege famously argues that these facts yield the result that there are really three kinds of reality:
1. The “outer world” of material objects
2. The “inner world” of sensations, mental images, feelings, wishes, inclinations, and other psychological states and entities
3. The “third realm” of thoughts or propositions
Realms 1 and 2 differ in four key ways. First, material objects are public entities, equally accessible to all observers. By contrast, psychological states and entities are private. Anyone can see the tree outside your window, but no one but you can “see” the mental picture you might form of the tree outside your window. Anyone can hear you stub your toe and the yelp you emit as a result, but no one but you can literally feel the pain in your toe. And so on.
Second, psychological states and entities have no reality apart from consciousness, whereas material things would exist whether or not we are consciously aware of them. Third, psychological states and entities therefore require an owner, a subject in whose stream of consciousness they are to be located. Material things, by contrast, exist independently of such subjects. Fourth and finally, each psychological state or entity has only a single owner, and cannot be shared with others. For example, your feeling of pain may be similar to mine, but it is not literally the same feeling.
Now, the entities of realm 3 are in some respects like and other respects unlike the entities of realms 1 and 2. Like the psychological entities of realm 2, propositions cannot be objects of perceptual experience. You cannot literally see the proposition that snow is white any more than you can see another person’s mental images or feelings. But like the material objects of realm 1, propositions are nevertheless equally accessible to everyone, are independent of consciousness, and have no single owner but are the common possessions of all.
To appeal to the traditional Scholastic distinction between the mind’s faculties, we can note that the objects of realm 1 are known through the senses, those of realm 2 are known through the imagination, and those of realm 3 are known through the intellect.
Needless to say, Frege’s talk of a “third realm” is reminiscent of Platonism, and he is typically regarded as a kind of Platonist. However, to accept the basic point he is making in the essay – the irreducibility of the entities of realm 3 to those of realms 1 and 2 – does not require that one endorse Platonic realism, specifically. One could instead develop the idea along either Aristotelian realist or Scholastic realist lines. (See chapter 3 of for discussion of these alternatives.)
As Frege notes, if, as psychologism claims, realm 3 were reducible to realm 2, there could in principle be no communication or disagreement between people. Suppose, to take an example from Frege, that a sentence expressing the Pythagorean Theorem conveyed nothing more than a psychological state or entity rather than a proposition. Then what I was referring to when I uttered this sentence (namely, some private denizen of my subjective stream of consciousness) would be completely different from what you were referring to when you uttered it (namely, some different private denizen of your own, different subjective stream of consciousness). We would not be talking about the same thing when we used the sentence. Hence one of us could not really teach the Pythagorean Theorem to the other, we could not really disagree about whether the other had properly understood it, and so on. Indeed, the supposition that we even genuinely understood each other would be an error, because there would be no common meaning we were both grasping.
Frege does not develop the point much further, but as other philosophers have argued, psychologism and other forms of relativism are ultimately simply impossible to formulate in a coherent way. They cannot possibly be correct. Indeed, the very attempt to formulate them presupposes their falsity. When you say, for example, that there are no true propositions independent of this or that particular human mind or collection of human minds, that claim is put forward as if it were itself true independently of the mind of the speaker and of anyone else’s mind. When you say that what we take to be true, and the laws of logic, reflect nothing more than the way that natural selection, economic or cultural forces, or the like contingently molded the human mind, you appeal to claims (about how natural selection and the relevant economic and cultural forces work) that are put forward as if they were true before human minds ever came on the scene. In defending such claims, you appeal to standards of logical argumentation as if they had an objective status that made them normative for all listeners, including those you are trying to persuade to endorse psychologism. And so on. (See chapter 3 of Five Proofs for further discussion.)
Practical and political implications
Frege says nothing about any practical or political implications his abstract metaphysical reflections might have. But there are such implications, and profound ones.
Politics is always to some extent given to ad hominem discourse, sentimentality, tribalism, and the like. But in recent years these tendencies seem to have spiraled out of control. Social media encourage kneejerk responses, groupthink, and relentless sarcasm and manufactured outrage in place of rational engagement. Traditional news outlets have largely abandoned the aim and even the pretense of being objective. Ideologies which rationalize the demonization of vast numbers of one’s fellow citizens and the peremptory dismissal of their views and concerns without argument .
Frege’s analysis reminds us of how literally illogical all of this is. Consider how typical it is today to evaluate claims and arguments in terms of how “offensive” they are to this or that group, or in terms of their association with some purportedly disreputable person or political persuasion. None of that matters in the least to whether a claim is true or false or an argument for it is cogent. A claim can be true and an argument a good one even if they are offensive, and a claim can be false and an argument bad even if they are pleasant. A disreputable person or party can put forward a true claim or a good argument, and an admirable person or party can put forward a false claim or bad argument.
In short, the truth and falsity of a proposition and the strength or weakness of an argument are entirely independent of the character and motivations of the people who present them and the feelings and concerns of those to whom they are presented. Deep down everyone knows this and is even happy to acknowledge it when doing so costs him nothing. But we can be extremely reluctant to do so when it might entail admitting that a political opponent has a point, that one’s own side is not as virtuous and well-informed as one likes to suppose, or that one’s tender sentiments are irrational and ought to be ignored rather than coddled. All the same, doing one’s best to acquire the habit of such objectivity is absolutely essential to being civilized and grown-up.
Or consider the imbecilic notion of “cultural appropriation.” As Frege reminds us, truth and logic float free of contingent human languages, and they float free of every other aspect of human culture as well. The denizens of the “third realm” are not anyone’s private property but rather the common possession of all rational beings. Naturally, there are moral reasons why a person might reasonably claim proprietary rights over some particular way of expressing an idea, as in a copyrighted book or movie. But ideas themselves are not the sorts of things it makes sense to regard as the property of any individual or group. Jewish, Christian, and Islamic thinkers of the Middle Ages who borrowed freely from the ancient Greek philosophers and from each other were not “stealing.” Rather, they were simply accessing the same ocean of truth that belongs to all of us equally, and in doing so increasing our understanding of it.
Most dangerous of all, however, is the “hermeneutics of suspicion” that evaluates ideas and arguments in terms of some hidden sinister group interest they are alleged to serve. This is analogous to the psychologism attacked by Frege, but writ large. For Marxism, the hidden interest in question is always that of some dominant economic class. For Nazism, it is that of some race or ethnicity that purportedly threatens the health and safety of one’s own Volk. For Foucauldian postmodernism, it is that of some ever elusive but omnipotent and omnipresent “power” that frustrates the indulgence of desire. And for Critical Race Theory and other brands of “wokeness” – which are essentially a synthesis of Marxian class analysis, Nazi racialism, and Foucauldian liberation from sexual and other social norms – it is “whiteness,” “colonialism,” “patriarchy,” “heteronormativity,” and other fantasized devil figures. Objectivity itself is dismissed by this insane worldview as a mere tool by means of which these bogeymen maintain their “oppression.” For the hermeneutics of suspicion, power alone, and not rational persuasion, is what matters.
The Marxists and the Nazis showed us where that mentality leads. We can be saved from a similar disaster only if enough of us have the clarity of mind and courage to refuse to concede a single inch to those who refuse to acknowledge and abide by standards of truth and logic that transcend all individuals, all races, all cultures, all class and political interests.
Notoriously, Frege himself privately held repellent anti-Semitic and anti-Catholic attitudes. That does not entail that he too ought to be “cancelled,” but, on the contrary, merely reinforces the lesson we ought to learn from him – that the value of a thinker’s philosophical ideas bears no essential connection to the defects of his personal character.