Immanuel Kant and the Critical Philosophy.
"The critical philosophy has nothing to do with a theory of the evolution of knowledge, in the modern sense of the word. Its distinctive task is to discover the necessary principles which must be presupposed—howsoever human nature may be constituted—if a mental function, no matter whether it be cognition, aesthetic or ethical evaluation, or religious trust, is to attain any valid results. It investigates the conditions of the validity of knowledge, not those of its origin".
