Body and Soul in Ancient Philosophy

462
Jonathan Barnes
an’s psychology is not bad theology, nor even good theology: it is bad
philosophy.
To see how that is so we may start from Tertullian himself. When
he considers the relationship between the soul and the mind, between
the anima and the animus, his conclusion is this: “You know that in
the soul there is a unity of substance, of which you should conceive
the mind to be an instrument and not a protector” (13.3). The mind
is not a part of the soul, still less is it a substance separate from the
soul, and least of all is it a superior substance which protects or governs
the soul. Rather, it is an instrument of the soul. It is an instrument for
thinking with: the mind itself does not think or ratiocinate – the soul
thinks and ratiocinates with the mind.
The mind is not a part of the soul if only because the soul has no
parts at all. Having mentioned various pagan opinions on the subject,
Tertullian urges that
these things will be held to be not parts of the soul but rather forces and
capacities and activities – as indeed Aristotle judged of some of them.
For they are not members of the soul’s substance but powers – powers
to move, to act, to think, and to do anything else of that sort you may
care to distinguish. So it is too with the celebrated five senses – sight, hearing,
taste, touch, smell. Although each of them has its own living-quarters
fixed for it in the body, that does not mean that this division of the soul
determines a partition of the soul. (14.3)
Sight, for example, has a local habitation in the body, presumably in the
eyes and the optic nerves. But that does not imply that there is a part of
the soul located in the optic regions: it is not that one part of my soul
sees, and another part hears – rather my soul (that partless and unified
substance) both sees and hears.
Tertullian calls the mind an instrument of the soul, and he does not
explicitly call it a power. He calls the senses powers of the soul, and he
does not explicitly call them instruments. Nonetheless, it is plausible to
think that he meant no distinction in status between the mind and the
other psychological items. Rather, the mind and the senses are, all of
them, both instruments and powers: sight is a capacity by means of
which the soul sees, mind is a capacity by means of which the soul
thinks.
Now that must seem pretty reasonable – up to a point. If anything
has seen the glory of the coming of the Lord, it’s not my eyes, nor a part
of my soul, nor one of my psychological capacities. My eyes can’t see,
nor can my soul, nor can any of my capacities. Nor, of course, can my