You say: **four terms: "reality", "phenomenon", "external world" and "thing-in-itself". While the first two or even three terms can rightly be postulated as identical**
No - phenomenon does not fit in this list - noumenon does. Noumenon is absolute reality, phenomenon is the world of appearance.
Kant does not say that any part of the "external world" (as you put it) can be illusory. Nor have I said that. The noumenal (let's call it that) is the epitome of reality; there's no illusory about it, by definition. It is, in Kant's view, true reality, at the deepest level (whereas what we normally call reality is in his view not really real).
In my view, the noumenal is - for us ordinary, unenlightened minds - speculative metaphysics. In this sense, paradoxically, it is imaginary. This is one of the perverted feats of Kant, that he has managed to posit what is effectively the most imaginary part of our belief-system as the most real. This paradox is what makes all irrationalists love Kant so much.
Also note, contrary to what you say, Kant does not claim that the noumenon is knowable (that is another paradox, in fact, since then there is no explanantion as to how he knows about it.)
As regards 'thing-in-itself', that is in Kant (as I understand it) identical with noumenon and reality. I do not know on what basis you claim it to be different.
With regard to Indian philosophy, as you say there are idealists and realists (as in the West). For the Idealists (the mind-only school) the very fact that knowledge of reality goes through consciousness means that reality is mental, or at any rate that it can only be claimed to be mental, since this is necessarily all we have. This may seem like a credible and consistent position at first sight; but if one thinks about it, it is inconsistent and therefore not credible. For to understand this position, we need to already have in our minds a distinction between the mental and the non-mental - and such distinction is prior in the course of knowledge, being based on the inductive course of ordinary knowledge. So mentalism is based on stolen concept. You cannot speak of 'mind' if you have not first experienced non-mind; the term is relative. This is what I previously referred to as 'dream', mental stuff. I do not agree with you that Indians understand induction.
Here again, I want to point out your personal error in identifying reality and external world with phenomenon. Phenomenon is appearance - which to mentalists means something in the mind, but to me means something neutral. The external world, in an ordinary perspective, refers to the world outside the mind, i.e. the body and the material (and eventually mental and spiritual) objects outside it. In the way you are using this term, I suspect you are referring to Kant's noumenal world, the world of things-in-themselves (as against things-as-they-appear, the phenomenal world). This corresponds to Indian philosophy's Absolute, the experience of which constitutes Nirvana.
I should add that, to my understanding, the world beyond this one, i.e. the spiritual world, the Absolute, the world of Nirvana, the noumenon, etc. - all this refers to One. It is NOT a multiplicity as worlds like 'things-in-themselves' suggest. It is singular. It is where the multiplicity of things meet, what they have in common, their common source. It is Monism. For me, that's God. Monotheism.
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Well, when I hypothetically identified "reality", "phenomenon" and "external world" I of course did it irrespective to Kant, so the term "phenomenon" here is certainly not Kantian. But your answer seems to suggest that you see some legitimacy in Kantian notions of "phenomenon" and "thing-in-itself". My main point on this matter is that "thing-in-itself" cannot be posited as existent, so I cannot understand what you mean by my supposedly "referring to Kant's noumenal world".
Of course Kant cannot claim that noumenon is knowable, but what I tried to show is that noumenon, when seen from Indian perspective, can only be phenomenon (not in Kantian sense), and in this status certainly knowable, although false. Further, I did not try to differentiate reality from thing-in-itself in Kant, but supposed that "external world" cannot be reduced to "thing-in-itself". That is to say Kant must presuppose external world to make more sophisticated conception of it (indeed split of it) in the form of "thing-in-itself".
What I want to pay special attention to concerning Indian philosophy is that all schools of it, both "idealists" and "realists", atmavadins and anatmavadins, theists and atheists etc. cannot conceive phenomenon without knowledge of it and precisely because of this cannot suppose unknowable and existent thing-in-itself. What I called "principle of knowledge" is thus more general consideration than the idealism/realism debate, and it seems to me quite compatible with the "principle of induction" (irrespective of its understanding by Indians) and your understanding of phenomenology. According to all this, the assertion that Indians identified real with mental seems to be forced at least. So, I certainly did not use the term "phenomenon" in the Kantian sense in my last message.
Hi Sentience. This is my last post on this string, as I cannot devote more time to this.
I reiterate that phenomenon refers to appearance - this is not just my opinion, but generally accepted. You have misunderstood this term, as well as (to a lesser extent) other terms you have been using.
I assumed that you actually read my booklet A Short Critique of Kant's Unreason, but it does not look like you did so. If so, I recommend you read this book. You should also first read the booklet Hume's Problems with Induction, to better understand the background of Kant. Most of all, I recommend you read my book Phenomenology.
Thank you for your interest. Best regards, Avi
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