كتاب الحيوان (Book of Animals)

"...and find its floor, air, and walls hot, yet we do not find them luminous. This is because in the earth and in the matter that has clothed the earth, there is much limitation and intertwined interpenetration, and there is no radiance within it. The heat of the fire had excited that heat and manifested it, but there was no radiance present for the radiance to excite and manifest it, just as heat connected with heat, displacing it from its position and bringing it forth from its place. Therefore, we found the floor, walls, and air of the furnace hot, but not luminous."

(Abu Ishaq claimed) that the proof that fire exists within stone and wood is the variation of directions. For it is incumbent upon anyone who denies this to claim that there is no oil in sesame and no oil in olives. Whoever says that must also say that there is no blood in a human being, and that blood is only created at the moment of incision. There is no difference between one who denies that the essence of aloe is bitter and the essence of honey is sweet before they are tasted, and the case of sesame and olives before they are pressed. If a claimant asserts that sweetness and bitterness are a'rad accidents, while oil and vinegar are jawhar essences/substances, then if this is required for one who speaks thus regarding the sweetness of honey and the acidity of vinegar—both being tastes—it must also be required regarding their colors. He would have to claim that the blackness of the plain, the whiteness of snow, the redness of safflower, the yellowness of gold, and the greenness of herbs only come into existence when a human views them, even if inspection and confrontation do not operate upon those essences.

(He said): If that speaker measures the color of a body after its taste, its length and width and form after its smell, and its lightness and heavy weight as he spoke of its softness and hardness, he has entered the gate of ignorance. He has joined those who claimed that a waterskin contains no air, even if they find it heavy to the touch, claiming it is only created when its ties are loosened. Thus, they should say the same regarding the sun, the moon, the stars, and the mountains when they are absent from their sight. He said that whoever flees from logical rigor to ignorance finds what he fled to even more burdensome. He used to tell a story for them, which I mention for its wit: (It is recounted) of a hunchback who fell into a well, his hump was leveled, and he developed a hernia in his testicle. A man congratulated him on the disappearance of his hump, and he replied, "What has come is worse than what has gone." Abu Ishaq claimed that Dirar ibn Amr had combined both disbelief and obstinacy in his denial of latency (kumun). He claimed that the belief in Divine Unity (tawhid) is not valid while denying latency, and that the argument for latency is only valid if there is blood in the human being, and it is merely something created upon viewing. He said he surely knew...