Immanuel Kant
Immanuel Kant was a German philosopher and one of the Enlightenment's main thinkers. Born in KΓΆnigsberg, Kant's comprehensive and systematic works in epistemology, metaphysics, ethics, and aesthetics have made him one of the most influential figures in modern philosophy. In his doctrine of transcendental idealism, Kant argued that space and time are mere "forms of intuition" which structure all experience, and therefore, while "things-in-themselves" exist and contribute to experience, they are nonetheless distinct from the objects of experience. From this it follows that the objects of experience are mere "appearances" and that the nature of things as they are in themselves is unknowable to us. In an attempt to counter the skepticism, he found in the writings of philosopher David Hume, he wrote the Critique of Pure Reason, one of his most well-known works.