A new method of thought
Post date: Mar 10, 2012 6:52:28 PM
Either I must assume that the concepts . . . conform to the object, or else I assume that the objects . . . conform to the concepts.
In the former case, I am again in the same perplexity as to how I can know anything a priori in regard to the objects. In the latter case the outlook is more hopeful.
For experience is itself a species of knowledge which involves understanding; and understanding has rules which I must presuppose as being in me prior to objects being given to me, and therefore as being a priori. They find expression in a priori concepts to which all objects of experience necessarily conform, and with which they must agree.
As regards objects which are thought solely through reason . . ., the attempts at thinking them (for they must admit of being thought) will furnish an excellent touchstone of what we are adopting as our new method of thought, namely, that we can know a priori of things only what we ourselves put into them.
Kant, Critique of Pure Reason, Preface to the Second Edition