Rationalism
The position that secure knowledge stems primarily from pure thought — classically in Descartes, Spinoza and Leibniz.
Rationalism takes pure thought to be the primary source and justification of knowledge: secure cognition is grounded in innate ideas given a priori, and on the model of mathematics the world is to be unlocked deductively from first principles. René Descartes, Baruch de Spinoza and Gottfried Wilhelm Leibniz shape its classical phase.
Kant, trained in the Leibniz-Wolffian school, later called this metaphysics “dogmatic” — it claims knowledge of God, the soul and the world without first examining whether reason is capable of any such thing. His transcendental philosophy sees itself as the settlement: rational structures, yes, but only as applied to possible experience.
Where it appears
Source: Wikipedia: Rationalism