faith. Without intending to give a compendium of metaphysics, Bahya furnishes in this first gate a system of religious philosophy that is not without merit. Unfamiliar with Avicenna's works, which replaced Neoplatonic mysticism by clear Aristotelian thought, Bahya, like many Arab philosophers before him, bases his arguments upon Creation. He starts from the following three premises: Nothing creates itself, since the act of creating necessitates its existence (see also Saadia, "Emunot," i. 2) the causes of things are necessarily limited in number, and lead to the presumption of a first cause which is necessarily self-existent, having neither beginning nor end, because everything that has an end must have a beginning all composite beings have a beginning; and a cause must necessarily be created. The world is beautifully arranged and furnished like a great house, of which the sky forms the ceiling, the earth the floor, the stars the lamps, and man is the proprietor, to whom the three kingdoms—the animal, the vegetable, and the mineral—are submitted for use, each of these being composed of the four elements. Nor does the celestial sphere, composed of a fifth element—"Quinta Essentia", according to Aristotle, and of fire, according to others—make an exception. These four elements themselves are composed of matter and form, of substance and accidental qualities, such as warmth and cold, state of motion and of rest, and so forth. Consequently, the universe, being a combination of many forces, must have a creative power as its cause. Nor can the existence of the world be due to mere chance. Where there is purpose manifested, there must have been wisdom at work. Ink spilled accidentally upon a sheet of paper can not produce legible writing. Unity of God Bahya then proceeds, following chiefly Saadia Gaon and the Mutakallimin ("Kalamists") to prove the unity of God (Arabic tawhid) by showing: All classes, causes, and principles of things lead back to one principal cause. The harmony of all things in nature, the interdependence of all creatures, the wondrous plan and wisdom displayed in the structure of the greatest and smallest of animal beings, from the elephant to the ant, all point to one great designer—the physico-theological argument of Aristotle. There is no reason for the assumption of more than one creator, since the world manifests but one plan and order everywhere. No one would without sufficient cause ascribe a letter written altogether in the same