Some background:
….300 years ago, physical science, while no longer in its infancy, was nonetheless still a toddler, and of more significance than what it’s done is what it hasn’t, the foremost of which is to dislodge Greek logic from its pinnacle of pure human thought;
….Kant was the chair of metaphysics and logic, of the Greek variety necessarily, from which it is reasonable to presume he must ground his original metaphysical thesis in the established logic he himself taught, even in the face of the as-yet unrealized enormous power of physical science;
….in Greek logic, the prime considerations are identity and contradiction: this is only this and never that. In Kantian duality conditioned by identity and contradiction there is no need of the excluded middle, but what is required are those conditions by which it is provable this is indeed only this and never that, which is accomplished by the mere definition. In a brand new philosophical structure having no procedural precedent whatsoever, it is simply a matter of validating a conception by defining what it’s supposed to do (A727/B755).
….the reader should always guard himself against putting words into Kant’s mouth, speaking for himself but calling it Kant. While Kant admits to constructing merely a theory, and acknowledges there is nothing to prove his theory is indeed the case, and recognizing the absolute necessity in sometimes leaving well-enough-alone, re: dismissing infinite regress as theoretically permissible by admitting there is that for which explanation is more confusing than beneficial (A496/B54), it remains internally consistent and logically united, which is all a theory is ever meant to be.
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Some groundwork:
….when Kant says his brand new metaphysics is complete, he means he’s given you everything you need to follow along, from the names of the faculties required to perform tasks, the names of the tasks required for the system to function, and their relation to each other and to the whole;
….beginning with a logical ground, coupled with specificity in definitions of terms, progressing through purposeful methodology, ending in a complete prescriptive intellectual system, results in a paradigm shift in philosophy itself. One can now take it or leave it, but he is not rationally justified in changing it.
….for Kant, in his speculative metaphysics, external things are given, such that no ontological conditions need be considered, insofar as what we think about and what we deem ourselves as having knowledge of as experience, is far less important than the method by which thought and knowledge are even possible in the first place;
….Kant’s system is in effect for each and every perception, every single one of them, ever and always, on the one hand, and congruently for each and every instance of pure thought on the other. The system cannot be turned on and off, it is a constant companion of the otherwise rational intellect, the fundamental condition of humanity in general. Hence the complexity of the philosophy itself, in accounting for how all that works, and why it should be that way;
…the Kantian system will not work for those thinkers for whom the dualistic nature of human cognition is indefensible, or downright wrong. One must acquiesce to human cognitive dualism, or stand aside from Kantian metaphysics.
Now, return to your seats ladies and gentlemen, boys and girls; the shows about to begin.
(OOOO!!! Aaron Copeland, aka, Emerson Lake and Palmer:
“Welcome back my friends
to the show that never ends.
We’re so glad you could attend
Come inside, come inside.
Come inside, the show's about to start
Guaranteed to blow your head apart
Rest assured you'll get your money's worth
The greatest show in Heaven, Hell, or Earth
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What's pertinent here, then, is the term noumenon or noumena, already given in Greek logic, the modern version only so for statements regarding, not of what it is as that was left unchanged from the Greek, but its origin, its validity and the placement in the new system it may or may not occupy;
….understanding is the faculty of thought, thought is represented in conception, conception is the spontaneity of thinking;
….I can think whatever I please (fn, Bxxvi), understanding being the faculty of thought, understanding then, is the origin of thinking whatever I please;
….a problem with thinking whatever I please, a problem with understanding being the origin of any thought whatsoever, is that understanding has no limit imposed on itself by itself. (A238/B297)
….before anyone objects, that understanding is regulated by rules of logic, it must be remembered understanding the faculty (the origin of conceptions) is not understanding the cognitive activity (the synthesis or conjoining of conceptions to each other). The faculty understanding is not under the rules of logic, these belonging to judgement, which informs of the correctness of synthesis but not of the spontaneous origin of conceptions synthesized;
….because it is not contradictory for understanding to merely originate conceptions, it is perfectly warranted to originate any conception it can think, any conception which arises spontaneously from it, is legitimate merely from being thought;
….there is nonetheless a control for understanding; it is reason, which has nothing to do with experience (A302/B359).
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….the standing definition of noumenon, established by the Greeks and left undisturbed in Kant, is simply that object of thought. Period. No more, no less. An object of thought in Kant, however, is a conception, from which follows noumena in Kant is merely conception. Period. No more, no less.
….in the Kantian system, conceptions in general are necessary but conception alone is useless. To think a conception, to have the spontaneous origin of one given, signals an end in itself (thoughts without content are empty, A51/B75), insofar as there is nothing to conjoin to a single conception, a singular instance of spontaneous thought, thus it is that noumena is an empty conception;
….an empty conception such as this, while valid and non-contradictory, is therefore called noumena represented in a negative sense, meaning to indicate that conception representing a thing, not a thing of sensible intuition which is already called phenomenon, but a thing of thought alone for which there is no intuition of any kind at all. (The faculty of thought does not intuit, the faculty of intuition does not think. A52/B76, this is this and not that, a fundamental ground of dualistic transcendental philosophy)
But….why?
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…there is no why, or, any why makes no difference with respect to any other why. Kant used mathematics to prove the possibility and validity of synthetic
a priori cognitions, and by the same token used noumena to prove understanding can think whatever it wants, and by association I can think whatever I please. He would have been logically inconsistent and his metaphysics would not be complete, if he proclaims I can think whatever I please, then not present a worthless example as easily as the worthwhile, of doing it;
….so the why understanding does its thing having been said, that being just because it can, still leaves the why of the uselessness of the conception itself, other than the fact it is a singular thought, which reduces to….why is it only a single thought, and, why does it follow that because it is a single thought it is unknowable;
….understanding is the source of conceptions, thought is the synthesis of conceptions. To synthesize conceptions presupposes a relation of separate instances of them, from which follows that in understanding….more correctly judgement, most correctly imagination….to synthesize conceptions, it must seek from itself through spontaneity of thought, or from consciousness through the collection of all antecedent cognitions, those conceptions to be conjoined;
…any synthesis of conceptions in understanding is for the express purpose of cognizing empirical objects; there is no other use of understanding in its empirical sense except experience (A237/B296);
….given that understanding is for the express use for experience, any conceptions imagination uses in its synthesis towards cognition of things of experience must themselves be empirical conceptions;
….that to which all empirical conceptions point, is sensibility, insofar as all empirical conditions whatsoever, arise externally from and are given to the system through the senses;
…the origin of those necessary conditions for the empirical understanding of existent things by means of the cognition of their representations, then, is intuition, from which follows that which imagination synthesizes with conceptions in understanding, must come from intuition;
(To shorten it up, I leave out the origin of phenomena, which represents the synthesis of conceptions in intuition, and thereby the separation of aesthetic sensibility from logical understanding)
…but for noumena, again in its negative sense, originating not externally and given to the senses, but spontaneously arising from thought alone, there is no phenomenal representation from which imagination in understanding uses in its synthesis of conceptions into a cognition;
…hence, noumena remain an empty conception, meaning there are no intuitions to conjoin with it, and for which the express purpose of understanding for the possibility of experience, is therefore denied to it.
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….a citation from Kant where he explicitly says that the noumenon is not the thing in itself…. — Janus
….there isn’t one, but the reader’s sufficient familiarity with the thesis as a whole can grasp the fact Kant wants….actually needs….it to be understood they are nowhere near the same. In fact, they cannot be the same and have the text maintain its accordance with established logic;
….sufficient familiarity looks like, Kant specifically states the understanding treats noumena as it treats the thing it itself (A255/B310), insofar as they both originate as single conceptions, meaning neither of them have conceptions subsumed under them, meaning neither of them relate to cognizable things. Just understanding once more thinking whatever it wants, the difference here is, the thing in itself, while not cognizable as such, still has validity because of what it is not;
….the fact noumena represents things that cannot be cognize says nothing about the things that can, and noumena cannot because they lack intuition, they lack intuition because there is nothing given to sensibility relating noumena to the pure forms of intuition, space and time;
….that which can be cognized, then, does have associated intuition, which then requires an exposition for the possibility of intuition;
….for the possibility of intuition is the necessity of an external object given to the senses, which is called a undetermined object of empirical intuition (A20/B34), or, an appearance in the sense of being presented to, as opposed to looking-like. Appearing to, not appearing as;
….all well and good, but the thing that appears was at some time that same thing which didn’t, or hasn’t, or won’t, appear, in which case it is nonetheless an object, just that object having no effect of he senes, or, which is the same thing, isn’t an appearance;
….but the thing given must be distinguished as to its causality, either it is given merely from being perceived, or, it is given because it was already a real, physical existent, for otherwise we are forced to affirm the appearance of something without that which appears (Bxxvi), the thing…without the thing, the thing now…the thing before now;
….it is much more rationally determinable, and much less potentially contradictory, to grant the thing given to sensibility was an already real, physical existent, which still begs the question as to what it was before became an appearance, which is for the understanding alone to discover;
….understanding thinks its conceptions, therefore to think the thing before appearance, to think the conception and represent it as the thing-in-itself, is a perfectly legitimate activity of understanding in its transcendental sense, meaning thought with respect to all cognitions in general, not just this or that particular cognition.
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…..provide a coherent distinction between the two concepts. I can see a distinction between things in themselves and the noumenon…. — Janus
Noumenon and thing-in-itself are both objects of thought, neither are appearances to sensibility, therefore neither are knowable through discursive cognition (A260/B315);
Noumena are not knowable because they have no intuition, they have no intuition because, as an object of thought, there is nothing to give to sensibility to intuit in any time;
The thing in itself is unknowable because it has no intuition, it has no intuition because as an object of thought, the thing-in-itself is not given to sensibility to intuit at any time, but there is a change of state through one time, wherein the thing-in-itself as conception becomes the thing of existence, and that is what appears;
That thing-in-self, upon being subjected to sensibility as an appearance hence no longer in itself, then becomes experience, its representation resides in consciousness, therefore does not revert back to being in itself when not perceived, but we can still think of it as it was when it was a thing-in-itself, only now it is thought as a thing in general. Discursive thought from conception becomes transcendental thought from an idea.
My version of coherence, while leaving out a lot of detail.
Thanks for asking. Hope I didn’t disappoint. Got questions, ask.