When was Kantian philosophy developed?
Immanuel Kant
In one of Kant's major works, the Critique of Pure Reason (1781),[22] he attempted to explain the relationship between reason and human experience and to move beyond the failures of traditional philosophy and metaphysics. Kant wanted to put an end to an era of futile and speculative theories of human experience, while resisting the skepticism of thinkers such as David Hume. Kant regarded himself as showing the way past the impasse between rationalists and empiricists which philosophy had led to,[23] and is widely held to have synthesized both traditions in his thought.[18]
A priori and a posteriori
The 18th-century German philosopher Immanuel Kant (1781) advocated a blend of rationalist and empiricist theories. Kant says, "Although all our cognition begins with experience, it does not follow that it arises [is caused by] from experience" According to Kant, "a priori" cognition is transcendental, or based on the "form" of all possible experience, while "a posteriori" cognition is empirical, based on the "content" of experience. Kant states, "[…] it is quite possible that our empirical knowledge is a compound of that which we receive through impressions, and that which the faculty of cognition supplies from itself sensuous impressions [sense data] giving merely the "occasion" [opportunity for a cause to produce its effect]." Contrary to contemporary usages of the term, Kant thinks that "a priori" knowledge is not entirely independent of the content of experience. And unlike the rationalists, Kant thinks that "a priori" cognition, in its pure form, that is without the admixture of any empirical content, is limited to the deduction of the conditions of possible experience. These "a priori", or transcendental conditions, are seated in one's cognitive faculties, and are not provided by experience in general or any experience in particular (although an argument exists that "a priori" intuitions can be "triggered" by experience). 