n the animal, just as the origin of the animal
reaches back into the plant world. Indeed, Aristotle anticipates the
discoveries of modern science, placing the vegetative and animal souls
beside the spirit of man. Thus motion and sensibility form the lower
boundary-line of the animal kingdom, and self-consciousness and
self-determination are the criteria of humanity.

Yet this very self-conscious freedom which forms man's personality, his
_ego_, lifts him into a realm of free action under higher motives,
transcending nature's law of necessity, and therefore not falling within
the domain of natural science. Dust-born man, notwithstanding his earthly
limitations, in spite of his kinship to mollusk and mammal, enters the
realm of the divine spirit. In the Midrash the rabbis remark that man
shares the nature of both animals and angels.(652) Admitting this, we feel
that he is tied neither to heaven nor to the earth, but free to lift
himself above all creatures or sink below them all.

6. Endowed with this dual nature, man stands in the very center of the
universe, and God esteems him "equal in value to the entire creation," as
Rabbi Nehemiah says of a single human soul.(653) Rabbi Akiba stresses the
image of God in humanity when he says: "Beloved is man, for he is created
in God's image, and it was a special token of love that he became
conscious of it. Beloved is Israel, for they are called the children of
God, and it was a special token of love that they became conscious of
it."(654) The Midrash compares man to God in exquisite manner: "Just as
God permeates the world and carries it, unseen yet seeing all, enthroned
within as the Only One, the Perfect, and the Pure, yet never to be reached
or found out; so the soul penetrates and carries the body, as the _one_
pure and luminous being which sees and holds all things, while itself
unseen and unreached."(655) The conception of the soul is here divested of
every sensory attribute, and portrayed as a divine force within the body.
This conception, which was accepted by the medieval philosophers, is
thoroughly consistent with our view of the world. The soul it is which
mirrors both the material and spiritual worlds and holds them in mutual
relation through its own power. It is at the same time swayed upward and
downward by its various cravings, heavenly and earthly, and this very
tension constitutes the dual nature of the human soul.

Chapter XXXV. The Origin and Destiny of