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Philosophy/Kant and the noumenal world


QUESTION: I'm confused by Kant; not an original complaint, I know, but stil... My understanding of Kant is that we can never have understanding of the noumenal world. All fine.

Where I struggle is with the realm of transcendental ideas and metaphysics. I understand that our synthetic a priori parsing of the world must be grounded on the psychological, the cosmological and the theological, but how can this happen is we can have no knowledge of the noumenal, which is where, presumably, these concepts arise from?

And is Kant's understanding of ethics based on the idea that our grounding in the theological idea grounded our sense of moral duty? Again, surely this means we have at least an inkling of the noumenal?

So: is there a experiential iron curtain between the noumenal and our lived reality? Or can we infer the noumenal using practical reason? And to which extent?

Thanks, S

ANSWER: Your questions indicate that you're thinking deeply about Kant and really engaging with him. Congratulations! thousands of (long...) books have been written on these questions.

When dealing with Kant, my first response is, "context, context, context." Kant had a project going. He wanted to "...limit knowledge to make room for faith." To do that, in his historical/cultural context, he had to overcome the (then...) radical skepticism of Hume, which he thought threatened BOTH faith AND the emerging natural sciences.

His solution was this: within the range of vision afforded by the goggles of our "forms of intuition", we CAN have sure PHENOMENAL knowledge. This saved the natural sciences. We CAN have secure a priori knowledge. Math and logic are saved!

But there's a "more" -- the self itself, obviously real (see Descartes) but known only by self-observation, the moral law -- that are clearly not phenomenal. They must be noumenal.

Kant's deduction of the noumenal has a great deal in common with the Medieval theologians' idea of the "via negativa" - we can never say what God is, only what She is not.

The origin of concepts interested Kant only to the extent that he needed to show that Hume was wrong in thinking none of them necessary. There is little textual material to mine there.

I view Kant's morality as self-grounding -- it's based on the notion that there is a set of maxims that ANY rational agent would have to accept to avoid contradiction in action. It does not, in my view, depend on theology.

In sum, I think the best answer to your questions is this: the noumenal is always inferred, never experienced -- that's what makes it the noumenal. We know it's there because we have knowledge that we could have only if it IS there. But the knowledge that we have BECAUSE of it is not knowledge OF it.

(Excuse the caps -- the AllExperts editor won't do italics.)

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QUESTION: Thanks; been rereading a couple of his works (in translation, sadly) but think I understand what might be confusing me. Isn't Kant trying to have his cake and it eat though? If the noumenal world is unknowable but informs our a priori weltanshaunng, then surely our inference of the noumenal from this self knowledge means it is knowable, even only if vaguely?

Am I going awry with my reading of these too?

- with his ethical system, Kant seems insistent that we must have free will for an act to have a moral dimension, and we are to rationally choose that which leads to Summum Bonum. If we have an objective sense of moral duty, aren't we irrational if we ignore it? In which case, isnt neglecting our moral duty irrational, and therefore not a moral choice at all? And isn't acting morally only reasonable as we have the inner sense of objective moral duty- what if this inner sense is missing. Sociopaths, for example: would they be acting immorally if they stole or killed if they possessed no sense of moral duty?

- Kant presents God as a 'postulate' of practical reason, as the part of his presented ethical framework that is morally (not logically, as he establishes elsewhere that the existence of God, as part of the noumenal world, cannot be deduced nor induced through pure or practical reason) necessary to ensure the Summum Bonum. This seems to follow the form;
1. for moral choices to have any power/reality/point there must be a Summum Bonum that results;
2. the only thing able to ensure the Summum Bonum is God;
therefore God is morally necessary.

This seems suspiciously like logically trying to prove God to me, no?

Am I failing to appreciate the difficulties in explaining the Kantian project, or are there apparent paradoxes that only become clear as one ponders the dialectic, as it were?

And wouldn't Hume just brush all this off as sophism? Wowon man nicht sprechen kann, daruber muss man schweigen & all that?

If any philosopher had,in fact, succeeded in solving all the problems of philosophy (as Wittgenstein famously claimed he had in the Tractatus Logico-Philosophicus), the subject would have ended there, It didn't, so there are clearly (real or perceived...) problems with Kant

Some historians of philosophy have said that philosophy oscillates perpetually between Plato's world and Aristotle's -- in one, the "real" is ideas, accessed purely mentally, and all else is "less real", but not illusory. For Aristotle, the "real" is stuff, about which we have ideas. That is a vast oversimplification, but it gives the flavor. Ideas make stuff, or stuff makes ideas. Every philosopher is somewhere along that spectrum.

Kant makes no commitments about whether the noumenal is stuff or ideas.(How could he?) He tries to bound metaphysics within the knowable (limiting knowledge to save room for faith). He tries to leave room for there to be something to have faith IN. (The noumena.) He tries to save physical science, mathematics, and logic from Hume's skepticism.

Yes, the cake must be had AND eaten. As I said earlier, he has a project!

Yes, we do have an objective sense of moral duty, and yes, we are irrational if we ignore it.

It's a misreading of Kant to think he thinks we have a "moral SENSE" the way the Scottish school thought. He thinks that every rational being will make the same moral choices when confronted with the same facts, but that is purely an intellectual faculty involved.

Your thinking that the moral doctrine is a backdoor way to prove the existence of God comes from reading Kant's morals as consequentialist. Consequentialists think that the moral value of an act is measured by its outcome. Kant definitely opposes this. He's a deontologist, he thinks the SOLE determinant of the goodness of an act is intent -- which is why he says that the only thing that can truly be called good is a good will.

The goodness of a good will comes from its FORM, not its object.

The ultimate question is, does Kant's project succeed? The professional consensus now is that it does not. It it illuminating? Very. Any philosophy that marks off certain parts of reality as unknowable is going to run into exactly the same problems.

I don't think we can predict Hume's reaction to Kant. Hume had an open mind. I think he ultimately would have come, as the profession generally has, to regard Kant's project as a failure, but I think he would have enjoyed the debate immensely.

Kant's biggest contribution, I think, is forcing us to think much more carefully about what we mean by "knowledge."




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Charles K. MacKay


I can answer a number of questions in philosophy; my academic concentrations (graduate school at Cornell) are ethics, political philosophy, and 19th-century German philosophy (Marx, Hegel, and hangers-on.)



BA, New College, 1971, Philosophy and Religion
Awarded four graduate fellowships upon graduation

MA, Cornell University, 1974
Social and Political Philosophy, Danforth Fellowship

All course work and dissertation drafts completed for Ph.D. Cornell University, 1971-1975, Social and Political Philosophy, Danforth Fellowship

Courses in statistics and microeconomics, George Washington University and The American University, 1976-1978

EXPERIENCE: Health Insurance Specialist 2005 - Present
Centers for Medicare and Medicaid Service
US Department of Health and Human Services

Allentown Business School Instructor (Computer Science) 2003 - 2005

Northampton Community College
Adjunct Professor of Philosophy 2003 -2005

Lehigh County Community College
Adjunct Professor of Philosophy and Computer Science


Medicare Made Easy (with Charles B. Inlander) Addison-Wesley, 1989

Good Operations, Bad Operations (with Charles B. Inlander) Viking Press, 1993

Health Rebooted: Information Changes Everything (in press), 2008

Bachelor of Arts, Philosphy and Religion, New College, 1971 Master of Arts, Social and Political Philosophy, Cornell University, 1975

Awards and Honors
Danforth Fellowship, Woodrow Wilson Fellowship

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