a general conclusion is drawn from a number of ideas grouped together; and (iv.) al-hafiza or az-zakira, "memory," which preserves and records the judgments formed. Men and animals perceive pariculars by means of sense; man attains the knowledge of universals by means of reason. The 'aql or rational soul of man is conscious of its own faculties, not by means of an external, i.e., bodily sense, but immediately by the exercise of its own reasoning power. This proves to be an independent entity, even though accidentally connected with a body and dependent on that body for sense perception: the possibility of direct knowledge without sense perception shows that it is not essentially dependent on the body, and the possibility of its existence without the body, which follows logically from its independence, is the proof of its immortality. Every living creature perceives that it has only one ego or soul in itself, and this soul, says Ibn Sina, did not exist prior to the body but was created, that is to say, proceeded by emanation from the Agent Intellect at the time when the body was generated. (Najat, p. 51).
Under the head of Physics Ibn Sina considers the forces observed in nature, including all that are in the soul, save only that which is peculiar to the rational soul of man. These forces are of three kinds: some, such as weight, are an essential part of the body in which they occur; others are external to the body on which they act, and are such as cause movement
