whereas intuition concerns what does not involve one’s own action, such as the changing shapes of the moon as its position relative to the sun changes. In reality, it is a purely cognitive experience involving no action. What it yields, too, consists of particular, individual matters, which become general only through reasoning by analogy.

As for self-evident truths—the primary knowledge that Allah places directly in souls, without any intermediary, such as arithmetic, including the knowledge that one is half of two—they do not yield knowledge of any particular thing existing outside the mind. Examples include judgments concerning number and magnitude in the abstract, and the knowledge that things equal to the same thing are equal to one another. Whenever you make a judgment about something existing outside the mind, this can only be through sensory perception, just as with intellectual apprehension. For intellectual apprehension consists in understanding what you have learned through internal or external sensation, by apprehending general or particular meanings. As for apprehending universals whose individual instances exist outside the mind without any sensory perception, this is inconceivable.

When a person examines himself, he finds that he does not apprehend this independently of internal and external sensation with regard to universals conceived in his mind, such as one and two, the straight and the curved, the triangle and the square, the necessary, the possible, and the impossible, and other such things that he himself supposes and conceives. But knowing that what is thus conceived corresponds to something existing outside the mind, and knowing external realities, necessarily requires internal or external sensory perception.

When sensory perception and intellect work together—as when sight and intellect work together—it becomes possible to apprehend the existing realities in question and understand the universal judgment that applies to them