Then anyone who affirms real causes understands that the explanation is that like is drawn to like while its opposite withdraws from it. Thus, when the air grows cold, the surface of the earth and all that lies upon it becomes cold, so the heat retreats into the inner layers, warming the core of the earth and the water stored therein. For this reason springs are warm in winter, and the internal organs of animals are warm as well, so that they eat more in winter than in summer because the heat digests their food. In summer, however, the air is hot, outward surfaces heat up, and the cold recedes to the interior; the inside of the earth and of animals becomes cool, and the springs cool likewise. Hence water issuing from a spring is colder in summer than in winter, and the digestive faculty is weaker.

These and similar matters are ordinary, empirical observations, even though many of them take place without any action on the part of human beings.

The same applies to what is known of Allah’s way: His giving victory to His prophets and believing servants and His punishing of His unbelieving enemies. These, too, are established facts that serve as lessons, even though the one who reflects on them has no power to bring them about. A person may also learn through the deeds of another and thereby acquire experiential knowledge, even though he himself cannot perform those deeds.

Moreover, the factor that produces knowledge of empirical matters is the repeated conjunction of one phenomenon with another—either without qualification or together with an awareness of their correlation. This repetition is the same whether it occurs through one’s own action or independently of it; the circumstance that it results from one’s action has no bearing on the acquisition of knowledge. Consequently, there is no need to classify the one as a type distinct from the other, since both share the same causal ground for knowledge—except to make clear that empirical data embraces both categories, just as we say of sense-perception that it includes what a person apprehends through sight, hearing, smell, taste, touch, and the like.

Indeed, the differences among the varieties of sense-perception yield greater disparities in the kinds of knowledge than does the distinction under discussion, for vision perceives its object without directly contacting it, whereas taste, smell, and touch—