We cannot determine whether, independent of appearances, material objects consist of substances and their attributes standing in spatio-temporal or causal relations.

Kant can thus be seen to have made two major points about transcendental idealism. (1) Although he never questions the existence of something independent of our representations of it, he can claim to have shown that when it comes to the ultimate constitution of this reality as it may be considered independently of the way it appears to beings endowed with reason and (human) sensibility we can know nothing on theoretical grounds; on practical grounds, as we have seen, he insisted that we can rati