The second paralogism:
That thing whose action can never be regarded as the concurrence of many acting things, is simple.
Now the soul, or the thinking I, is such a thing.
Where is the fallacy of equivocation manifested in an ambiguous middle term?
What is the ambiguity of this paralogism?
Why is there an ambiguity?
Before we present Kant’s critique of this paralogism, we’d like to situate the discussion, albeit very briefly in the context of the theory of Descartes cogito ergo sum. It is also worth remembering that in his initial stage Kant himself had succumbed and asserted both the simplicity and immateriality of the soul, something he later refuted in his discussion of the paralogisms .
The thesis of the simplicity of the soul has a long history; it probably goes back to Plato’s discussion of the immortality of the soul in Phaedo. But in its modern version is mostly known through Descartes and Leibniz’ rationalist philosophies. We’ll not go into their theories here, but will only mention, in passing, a quote or two to make more understandable the problematic of Kant’s critique of Rational Psychology, as the doctrine of the soul constructed solely from the I think of apperception. Descartes introspectively says ,
When I consider the mind, that is, when I consider myself insofar as I am just a thing that thinks, I can distinguish in myself no parts, but know [my emphasis] and clearly conceive myself to be a thing single and entire.
In another place, he says:
The mind cannot be conceived except as indivisible [because] we are not able to conceive of the half of any mind.
The Rational Psychologist thesis of the soul is that it is a substance, as in the first paralogism, and simple, as in this paralogism, and therefore not an aggregate or a composite. Simplicity is here hardly distinguishable from substantiality. The idea seems to be that “the soul is simple” simply means that it is not divisible into two or more substances. Because if it were composite, that is, an aggregate of many, then there could be no synthetic consciousness of the object as a whole. For a whole of parts to be cognized there must be a single subject which cannot be composite of parts. The multiplicity of representation presupposes the absolute unity of the thinking subject. The unity of consciousness is a phenomenon which exists whenever consciousness exist, a single self-conscious subject must, therefore, head the unitary complex of thought. “For” as Kant summarizes/represents the doctrine in (A352)
“suppose that that the composite were thinking; then every part of it would be a part of the thought, but the parts would first contain the whole thought only when taken together. Now this would be contradictory. For because the representations that are divided among different beings (e.g., the individual words of a verse) never constitute a whole thought, (a verse), the thought can never inhere in a composite as such. Thus it is possible only in one substance, which is not an aggregate of many, and hence it is absolutely simple”
That is to say, the subject of thought cannot be resolved into a plurality of subjects. Should that which thinks be viewed as composite, or should the thought subsist in a composite, or in many representations without a grounding in the absolute unity of the “thinking subject”, then a multiplicity of separate consciousness would result, and there would be no way to identify the simple substance as the unity of thought.
Kant argues differently, although he admits that he cannot answer the question of “What is the constitution of a thing that thinks?” a priory, because that would require a synthetic answer. Kant cannot give a synthetic solution because the manifold of intuitions is necessary (A398). He maintains that the Rational psychologists are led astray by not distinguishing a subtle ambiguity in the use of one of the crucial terms of the syllogism.
What is their mistake according to Kant?
They mistake a transcendental claim for an empirical one. Put differently, they conflate the transcendental use of a particular concept of the major premise and the empirical concept of the minor premise and conclusion. Kant object on two grounds:
1) “The so-called nervus probandi of this argument lies in the proposition that many representations have to be contained in the absolute unity of the thinking subject in order to constitute one thought. But no one can prove this from concepts” (A352).
This proposition cannot be proven from concepts, i.e., analytically, because they “give no extended cognition of that on which thinking rests as to its possibility” (A398). The unity of thought consisting of many representations is collective. The necessary unity and simplicity of thought/subject cannot be proven nor inferred from the concepts because it can be, among others, related to (or originated from):
a) the collective unity of the substances cooperating in it (body and its parts),
b) it can be a causal by-product of blind interactions among the simples,
c) just as it can to the absolute unity of the subject.
There is thus no necessity in presupposing a simple substance for the composite thought according to the rule of identity.
Neither can the proposition be cognized synthetically a priory:
2) “It is also impossible to derive this necessary unity of the subject, as a condition of the possibility of every thought, from experience. For experience gives us cognition of no necessity”.
Kant is saying that the necessary unity of the subject can be derived neither from pure concept nor from experience. The soul is not an object of possible experience. It is merely formal-logical unity. The Rational psychologists thus err by illegitimately substituting one’s own subject for the object of cognition, for the claim of a subject of thought as a simple indivisible substance, and for claiming knowledge from concepts alone in absence of appropriate intuitions. “The simplicity of the representation of a subject is not eo ipso a knowledge of the simplicity of the subject itself”. Now Kant admits that the subjective I, the “I” of apperception, (as the representation of the synthesis of the manifold of intuition) accompanies and is presupposed in all thinking and cannot be distributed among many subjects, it is characterized transcendentally as a unity presupposed in all experience. He nevertheless denies that we can know or cognize anything about it.
But the simplicity of myself (as soul) is not really inferred from the proposition “I think,” but rather the former lies already in every thought itself… But I am simple signifies no more that that this representation I encompasses not the least manifoldness within itself, and that it is an absolute (though merely logical) unity (A355).
They [the attributes that I ascribe to Myself as a thinking being in general] are nothing more than pure categories, through which I never think a determinate object, but rather only the unity of representations in order to determine their object. Without an intuition to ground it, the category alone cannot yield any concept of an object; for only through intuition is an object given, which is then thought in accordance with the category… When I call a thing simple in appearance, then by that I understand that its intuition is of course a part of the appearance, but cannot itself be further divided, etc. But if something is cognized as simple, only in the concept and not in appearance, then I really have no cognition of the object, but only of my concept, which I make of something in general that is not susceptible of any real intuition (A399/400).
So the mistake in this paralogism, as in the first one, according to Henry A. Allison lies in “the conflation of the unity of consciousness required as a logical condition of thought with the real metaphysical unity (simplicity) of the thing that thinks”. This conflation then rests on the illusory hypostatization – hypostatization being taken as what merely exist in thought to be a real object existing outside the thinking subject (A384) – of this subject under the direction of P2 as a metaphysical assumption that purports to be objective – the illusion consist in something subjective presenting itself as objective .
In a nutshell: according to Allison and Michelle Grier’s interpretation – an interpretation taken from Kant himself in (A402) – of the first paralogism that the concept “substance” in the major premise is used transcendentally (in abstraction from the conditions of our sensible intuitions) and the same concept in the minor premise is deployed empirically, and based on her further claim that indeed all paralogisms follow the same pattern, then the conclusion seems to follow as if by itself: the major premise of this paralogism makes a transcendental use of the concept simple, whereas the minor premise and the conclusion use the same concept empirically (in a way which presupposes that some object has been so given). In applying the concept of the simple to the “I” of “I think” the Rationalist Psychologist is illegitimately assuming that the subjective “I” is an object which could be subsumed under the concept of simplicity. The second paralogism falsely argues from the logical unity of the subject in representation to the actual simplicity of the subject in itself. “One can place the illusion” says Kant, “in the taking of a subjective condition of thinking for the cognition of an object” (A396) .
The idea behind the simplicity of the soul leads to the immateriality of the same, leading to the view that the soul is wholly distinct from the body, or as Kant puts it “the soul is not corporeal” (A356/7). Now bearing in mind that Kant is making not a dogmatic or sceptical but a critical objection to paralogisms (A389), the issue of corporeality or spirituality of the soul will not be pursued here, but it suffices to say that the Rational psychologists are guilty of transcendental realism (the view which consists in conflation of appearances with things in themselves). As Kant, in a rare moment of clarity, says, “if matter were a thing in itself, then as a composite being it would be completely distinguished from the soul as a simple being” (A359). But since, as the transcendental aesthetics has proved, bodies are not things in themselves, but mere appearances of our outer sense, then “the real question at issue is not that of the distinction between the soul and bodies in space, but of the distinction between the soul and that something which conditions all outer appearances” , nor can we intelligibly inquire about its identity when perceived as a thinking being in itself with an appearance. (See also Kant, A358).