Kant

Immanuel Kant — Prussian philosopher who wrote the Critique of Pure Reason (1781) — the most influential work in modern philosophy — who argued that the mind imposes structure on experience (space, time, causality are frameworks of the mind, not features of things in themselves), synthesizing rationalism and empiricism.

Performed the Copernican revolution in philosophy — Kant argued that instead of the mind conforming to objects, objects must conform to the mind's categories; space, time, and causality are not discovered in the world but imposed by the mind on experience; the 'thing in itself' (Ding an sich) is forever unknowable — demolishing both naive empiricism and dogmatic rationalism.