Critique of Pure Reason
Experience depends on forms supplied by the mind, while knowledge has limits that speculative reason repeatedly exceeds.
Kant asks how knowledge that is informative yet not derived solely from observation can be possible. His proposed reversal is that experienced objects conform to the conditions through which humans can know them.
A window shapes what can be seen without inventing the entire landscape. Kant's question is similarly about the conditions of experience, not a claim that everyone manufactures reality at will.
Space and time are forms of sensible intuition; categories such as causality organise understanding. Knowledge requires both what is given in experience and the conceptual activity that makes it intelligible.
We know appearances under those conditions, not things as they might be independently of our way of knowing. This does not imply that each individual freely invents the world.
Reason generates illusions when it treats ideas about the soul, the totality of the cosmos, and God as objects of theoretical knowledge. Antinomies reveal conflicts produced by extending legitimate concepts beyond experience.
The conclusion limits speculative knowledge while preserving other roles for reason. Clarifying the conditions of a claim precedes deciding whether its conclusion has been established.
Some arguments never end because they demand a kind of proof their methods cannot provide. Kant makes the limits of a question part of the work of answering it.
Sensibility supplies intuitions while understanding brings them under conceptual relations.
The unity of consciousness makes connected experience possible across different representations.
A concept's legitimate use depends on the conditions of possible experience.
Reason seeks completeness and thereby exceeds what observation can establish.
The cosmological disputes arise from treating the world as a completed object.
Sensibility supplies intuitions while understanding brings them under conceptual relations.
What if some philosophical arguments never end because they demand knowledge beyond the conditions of possible experience?