In this lower world man is the noblest creature. By means of his soul he may attain eternal life as an individual like God and the angels (_i. e._, the Intelligences), whereas all other creatures of the lower world are permanent in species only but not as individuals. This is the meaning of the expression in Genesis, "Let us make man in our image," in the image, that is, of God and the angels. Man is a microcosm, a universe in little, for like the great universe he consists of a body animated by a soul.
As the noblest part of man is his soul, it becomes his duty to know it. He must know whether it is substance or accident, whether it will die when it is separated from the body, and for what purpose it was brought into union with the body. In order to learn all this one must first study the preparatory branches, grammar, logic, mathematics and physics. In the study of psychology we learn that man has three souls, vegetative, animal and rational, and the latter alone is immortal. It is a part of the world soul, having existed before it came into the body, and under favorable conditions will return again to the world soul when separated from the body. The condition which must be fulfilled by the soul before it can return to the world soul is the acquisition of wisdom, for this is the purpose for which it was put into the body, namely, in order that it may learn the work of its master and observe his commandments. There are many sciences, but they are related to each other, all leading up to the one highest science, the knowledge of God and his goodness. A person must advance gradually in studying the work of God from the knowledge of minerals, plants, animals, the human body, to the knowledge of the spheres and heavenly bodies, the causes of eclipses, etc., and from this he will gradually come to know God. The commandments of the Bible are also of importance for this purpose. To understand the secret of the commandments is to gain eternal life. For wisdom is the form of the soul, and hence the soul does not die like a body.
The reward of the soul is re-absorption in the world soul of which it is a part, and the punishment of the unworthy soul that neglected to acquire knowledge is destruction. What Ibn Ezra means by the Hebrew word "abad" (ordinarily rendered to perish, to be destroyed) is not clear. It is hard to see how a pre-existing soul can perish utterly. Rosin suggests that Ibn Ezra is alluding to transmigration,[217] but it is not clear.