 If there did not lie in you a faculty for intuiting a priori; if this subjective condition were not at the same time the universal a priori condition under which alone the object of…intuition is possible; if the object ([e.g.,] the triangle) were something in itself without relation to your subject: then how could you say that what necessarily lies in your subjective conditions for constructing a triangle must also necessarily pertain to the triangle in itself. (A 48/B 65)