A History of Mediaeval Jewish Philosophy

by Isaac Husik

The basis of the four elements is a substance filling place as a result of its assuming the form of corporeality, i. e., extension in three directions. Filling place, it moves; moving, it becomes warm. When its motion is completed, it necessarily comes to rest and becomes cold. Heat and cold are the active powers, wet and dry are the passive qualities, wet being associated with heat, dry with cold. The mixture of these qualities with the corporeal basis results in the four elements.

The three natures, mineral, plant, animal are composed of the four elements. When a seed is put in the ground it cannot grow without water, and sunshine and air. These form its food, and food is assimilated to the thing fed. Our bodies are composed of the four elements, because they are nourished by plants. The general process of the sublunar world is that of genesis and dissolution. The genesis of one thing is the dissolution of another. The dissolution of the egg is the genesis of the chicken; the dissolution of the chicken is the genesis of the four elements; for in the living being the elements are potential, and they become actual when the animal dies. This continuous process of genesis and dissolution proves that this world is not permanent, for the basis of its processes is change.[170]

The human body corresponds to the corporeal world, and is similar to it in its nature and matter. Man's body is subject to genesis and decay like other objects. It is composed of the elements and returns to them. It has in it the nature of minerals, plants and animals. It has the power of growth, sustenance and reproduction like plants. Man is like animal in having motion and sensation. He has the spirited power and the appetitive like other animals. His body is perfect because it has resemblances to all kinds of plants and animals. His body as a whole resembles great trees, his hair is like grass and shrubs. Animals have various qualities according to the relation of the animal soul to the body. Thus the lion has strength, the lamb meekness, the fox shrewdness, and so on. Mankind includes all of these qualities. In the same way various animals have various instincts resembling arts, such as the weaving of the spider, the building of the bird and the bee, and so on. They also subsist on various foods. Man alone combines all arts and all kinds of food.

The human body has three dimensions like inanimate bodies. It is also similar to the bodies of plants and animals, and at the same time is distinguished alone among animals by its erect position. This is due to the fact that man's nature is proportionate, and his body is purer and finer than other bodies. Thus we see when oil is pure, its flame rises in a straight line; when the oil is impure the flame is not straight. Another thing proving that man's nature is superior to that of other animals is that the latter live in that element which is akin to their constitution—fish in water, birds in air, quadrupeds on land. Man alone can inhabit all three. Another reason for man's erect position is that he is a plant originating in heaven. Hence his head, which is the root, faces heaven.[171]

Man has three souls, a plant soul, an animal soul and a rational soul. He must have a plant soul to account for the fact that man grows like other plants and dies like them. For if he can grow without a plant soul, plants can do the same. And if this too is granted, then there is no reason why mountains and stones should not grow also. Again, if man can grow without a plant soul, he can live without an animal soul, and know without a rational soul, which is absurd.

The faculty of the vegetative soul is the appetitive power, whose seat is in the liver. Its subordinate powers are those of nutrition and growth. Through it man feels the need of food and other natural desires. He has this in common with the lower animals. It is the first power that appears in man while he is still in his mother's womb. First comes the power which forms the combined seed of the male and the female into a human being in its proper form and nature. In doing this it requires the assistance of the "growing" power, which begins its activity as soon as the first member is formed, and continues until the period of youth is completed. This power in turn needs the assistance of the nourishing power, which accompanies the other two from the beginning of their activity to the end of the person's life. All this constitutes the plant soul, and it must not be supposed that these powers are separated from one another, and that one is in one place and another in another place. They are all spiritual powers derived from the universal powers in the upper world.

When the form of the being is complete, the animal soul makes its appearance. This soul is carried in the spirit of the animal or man, which is found in the pure blood of the arteries. There are two membranes in every artery, making two passages, one for blood and the other for the spirit or wind. The seat of the animal soul is in the heart, and it is borne in the pure red blood. This is why we see in the heart two receptacles; in one is spirit, in the other, blood. Hence after death we find congealed blood in the one, while the other is empty. Death happens on account of the defective "mixture" of the heart. This means that the four humors of which the body is composed, namely, blood, yellow and black gall and phlegm, lose the proper proportionality in their composition, and one or other of them predominates. An animal does not die unless the mixture of the heart is injured, or the heart is wounded seriously. Death is also caused by disease or injury of the brain. For the brain is the origin of the nerves which control the voluntary activities by means of contraction and expansion. If the chest does not contract, the warm air does not come out; if it does not expand, the cold air does not come in; and if the air does not come in or out, the heart loses its proportionality, and the animal dies. The functions of the animal soul are sensation and motion. This motion may be active as well as passive. The active motions are those of the arteries, and the expansion and contraction of the chest which results in respiration. The passive motions give rise to the emotions of anger, fear, shame, joy, sorrow.

Anger is the motion of the spirit within the body toward the outside, together with the blood and the humors. This is found in animals also. Fear is the entrance of the soul within, leaving the surface of the body, and causing the extremities to become cold. Shame is a motion inward, and forthwith again outward. Sorrow is caused in the same way as fear, except that fear is sudden, while sorrow is gradual. This is why fear sometimes kills when the body is weak. Joy is motion outward. Joy may kill too, when it is very great, and the person is weak and without control. Joy is of the nature of pleasure, except that pleasure is gradual, while joy is sudden.

Pain is that feeling we have when we are taken out of our natural state and put into an unnatural. Pleasure is felt when we are restored to the natural. Take, for example, the heat of the sun. When a person is exposed to it, the sun takes him out of his natural state. Heat is then painful, and pleasure is produced by the thing which restores him to his natural state; in this case a cold spring and a drink of cold water. Similarly a person walking in the snow and cold air feels pain by reason of the cold taking him out of his natural state. Heat then gives him pleasure by restoring him. The same thing applies to hunger and thirst, sleeping and waking, and other things which give us pleasure and pain. Without pain there is no pleasure, and the pleasure varies in accordance with the antecedent pain.

Life is the effect of the animal soul. The disappearance of the effect does not necessarily involve the disappearance of the cause, as the disappearance of the smoke does not require the cessation of the fire. Death means simply the separation of the soul, not the destruction thereof. It does not follow because the human soul remains after the death of the body, that the soul of the ox and the ass continues likewise, for the two souls are different. Animals were created for the sake of man, whereas man exists for his own sake. Moreover, man's life is ultimately derived from his rational soul. For if the animal soul of man were the ultimate source of life, the rational soul too would be dependent for its life upon the former, and hence would be inferior to it, which is absurd. It remains then that the rational soul gives existence to the animal soul in man.