العمليتان اللتان يقوم عليهما فهمنا، أي الحدس والاستنباط، واللتان قلنا إنّهما وحدهما نعتمد عليهما في اكتساب المعرفة.

“The two operations of our understanding, intuition and deduction, on which alone we have said we must rely in the acquisition of knowledge.”Rene Descartes — RULES FOR THE DIRECTION OF THE MIND DISCOURSE ON THE METHOD MEDITATIONS ON FIRST PHILOSOPHY OBJECTIONS AGAINST THE MEDITATIONS AND REPLIES THE GEOMETRY (1952)