immortal as an individual: it has a matter, quite apart from the intellect which
cognizes universals, and also apart from the form of the human body. Thus
there is no danger of falling into the Averroist position that only the intellectual
part of the soul is immortal by absorption into the world-soul Agent Intellect;
nor is there danger of implying that the soul dies with the body, as a form of
that body.
Aquinas, however, directly courts these difficulties. For him, the soul is the
form of the body—a traditional Aristotelean position. In hot debate against
the Franciscan Peckham in 1270, he held that the sole principle of life and of
intellect in man is the soul, thus making the body an integral part of human
nature, not an inferior dross to be shed by the spiritual part. How then to
avoid falling into the Averroist or materialist side? Aquinas’s creative stroke is
to attack a more fundamental metaphysical point: he overturns the accepted
argument, which Bonaventure had taken from Avicenna, that essence, what a
thing is, is a higher reality than existence, as if the fact of something’s existing
were merely an accident tacked onto its essence. This was a Platonic way of
looking at the world, in which eternal essences come down from the spheres
below God into the realm of mere temporal existence.
Aquinas reverses the situation: essence is merely potentiality, which be-
comes actual only by the act of existing. But here he goes against traditional
Aristotelean views as well, since Aristotle had held that matter is potentiality,
given actuality by form. Aquinas presses onward, rearranging these concepts:
composite substances of the ordinary world are made up not only of matter
and form, but of essence and existence as well. The essence of the human body,
for instance, is a combination of matter and form; and both of these are
actualized, drawn from the realm of mere potentiality, when they come into
existence.
This became the rallying point of the Thomists, the doctrine of the unity
of form in the composite. A composite essence is made up out of all the forms
that are applicable (e.g., a man shares in the forms of human, rational, animal,
etc.). This doctrine allows for full participation in the reality of the material
world, and for sensory knowledge, while holding on to Christian doctrine of
individual immortality and bodily resurrection. The cost, however, was to
overthrow prevailing Platonist and Augustinian metaphysics and epistemology.
Applied to God, Aquinas’s concepts meant that God is a composite of Form
and Act, not a Form of all forms, as in the Neoplatonic tradition carried on
by Aquinas’s own teacher, Albert. Nor is God preeminently the locus of Ideas,
as in the Augustinian version defended by Bonaventure. Nor is God a mystical
One beyond being, since Aquinas argues that One is only a division of being.
Aquinas’s compromise, together with the weight of Aristotelean thinking
in both heretical and nonheretical guises, completely reconstructed the premises480 •^ Intellectual Communities: Western Paths