Immanuel Kant
Immanuel Kant (; ; 22 April 1724 – 12 February 1804) was a German philosopher who is a central figure in modern philosophy. In his doctrine of transcendental idealism, he argued that space, time and causation are mere sensibilities; "things-in-themselves" exist, but their nature is unknowable. In his view, the mind shapes and structures experience, with all human experience sharing certain structural features. He drew a parallel to the Copernican revolution in his proposition that worldly objects can be intuited "a priori" ("beforehand"), and that intuition is therefore independent from objective reality. Kant believed that reason is the source of morality, and that aesthetics arise from a faculty of disinterested judgment. Kant's views continue to have a major influence on contemporary philosophy, especially the fields of epistemology, ethics, political theory, and post-modern aesthetics.
T. K. Seung
"Kant: A Guide for the Perplexed" (2007) provides an overview of Kant's philosophical development. This development has been understood as his struggle to reconcile continental rationalism and British empiricism, which has produced his a priori formalism. But this is only one half of the story, according to Seung; the other half is Kant's normative Platonism. In Kant's own language, Seung says, his philosophy consists of two types of elements: transcendent and transcendental. The transcendental elements are a priori and innate to the subject of experience. The transcendent elements transcend the world of experience. The former was Kant's appropriation of the Cartesian legacy; the latter was his adaptation of the Platonic legacy.