McCorrama asks the following question:
"Given your prior comments on science, and the importance of the Critique of Pure
Reason can you offer any guidance in approaching the material which deals with
the problems of contemporary physics/cosmology.
"Lee Smolin in 'The Life
of the Cosmos': Kant claims to disprove Leibniz's principle of sufficient
reason, which is the basis of his relational philosophy of space and
time...Kant's writings on space and time claim to establish the logical
necessity of both Newtonian mechanics and Euclidean geometry...I find Kant's
presumption to define a domain of discourse in which final conclusions could be
reached, which limits once and for all what we might perceive about the world
highly implausible (even leaving out the fact that they led Kant to conclusions
we now know are false)."
Needless to see, this is a very large question, and one about which I claim very little expertise. Perhaps I can limit myself to the quoted remark about the views of Kant, which is a subject about which I know something.
When reading Kant [or any philosopher], it is always useful to draw a sharp distinction between what the philosopher's arguments actually prove, assuming they are sound, and what the philosopher says his or her arguments prove. Just as novelists are often poor guides to the literary interpretation of their own works, so too philosophers cannot always be trusted as judges of what their arguments show.
For example, the arguments in the Transcendental Aesthetic of the CRITIQUE actually show, if they are correct, that there is a mathematics of space that is knowable a priori even though many of its propositions are synthetic. This seems on the face of it impossible, and Kant's theory of forms of cognition lying a priori in the mind is intended to explain how it could be possible. The kicker, of course, is that the propositions are true only of things as they appear to us, of phenomena, and not of things as they are in themselves, of noumena. Now, Kant was familiar with Euclidean geometry, which was, in his day, the gold standard for mathematical knowledge. So he naturally, and quite illegitimately, concluded that his arguments establish the knowability a priori of the propositions of Euclidean geometry. But if you examine the text of the Aesthetic closely, you will find that there is not a word in it about the axioms and definitions of traditional geometry.
In much the same manner, Kant undertakes to establish the knowability a priori of the principle that everything that happens in space and time has a cause [the so-called Causal Maxim], but this claim, if indeed he is successful in establishing it, tells us nothing at all about Newtonian Mechanics. Once again, Newtonian mechanics was in Kant's day the gold standard for scientific knowledge so he simply assumed that he was demonstrating the knowability a priori of Newton's theories. In this case, Kant did in fact write a book claiming to establish the particular propositions of Newtonian physics [his Metaphysische Anfangsgrunde der Naturwissenschaft], but this is a decidedly inferior work that no one take seriously.
None of this, of course, answers the question, Do Kant's arguments establish anything at all? That, as they say, is a subject for another day [and since this is the fiftieth anniversary of the publication of my book on the Critique, I will simply nod majestically to that work and move on.]
I hope this helps.