Kant's characterization of rationalism is generally accurate. One addition must be made. Like most early modern philosophers, the rationalists conceived of the human cognitive faculties as distinguished into the pure intellect, the senses, and the imagination. The pure intellect was the faculty that enabled human beings to gain knowledge. Rationalism may be defined as the view that substantive truths about the nature of reality may be derived from the pure intellect alone, operating independently of the imagination and the senses.
Science EncyclopediaScience & Philosophy: Quantum electronics to ReasoningRationalism - Rationalism Defined, The Roots Of Rationalism, René Descartes, Benedict Spinoza, Nicolás Malebranche, Gottfried Wilhelm Von Leibniz