 Unlike Aristotle, Avicenna also recognizes a broader division of causes into physical causes and metaphysical causes (Avicenna, [Ph], 1.10 [3]). The distinction is best approached by considering the Aristotelian division between substances and accidents as found in the ten categories. (Within the Aristotelian tradition, including Avicenna, the ten categories purport to provide the broadest classification of ways things are found (mawjūd) in the world; Avicenna, [Cat], 1.1 and [MPh], 3.1.) The primary category is that of substance, which for Avicenna is the existence that belongs to a thing through itself, for example, the existence that belong to a human as human or a dog as dog (Avicenna, [MPh], 2.1 [1–2]). Accidents are what exist in another, namely, in a substance, and include a substance’s quantity, quality, relation, where, when, position, possession, activity and passivity. Metaphysical causes involve what accounts for the existence and continual conservation of a substance, or, more exactly, of a concrete particular. Physical causes in contrast involve those factors that bring about changes in the accidental features of bodies, primarily changes of quality, quantity, location and position. For example, a father is responsible for seeing that his semen becomes located within the mother, and the mother ensures that the right womb temperature for the fetus is maintained and that the fetus is fed. Location, temperature, possession of nutriment and the like belong to categories of accidents, not to that of substance. Consequently, for Avicenna the father and mother are most properly physical agents, that is, the cause of accidental changes that prepare the matter for the form. As such the parents are not the cause of the existence of the offspring’s species form by which it is the specific substance it is. Instead, the metaphysical agent—the one who imparts the species form to the matter such that there comes to be a substance of the same kind as the parents—is a separate (immaterial) agent, which Avicenna calls the Giver of  Forms (Avicenna, [Ph], 1.10 [3]; [AP], 2.1; [MPh], 6.2 [5] &amp; 9.5 [3–4]).[1] 