[14]
scholastic doctrine, while retrenching the limbs and outward flourishes.
The doctrine of substantial form which he learnt in his youth had had
_something_ in it; he could not settle down in the principles of Descartes
or of Gassendi, because both ignored this vital _something_. Since the
requirements of a new science would not allow a return to sheer
scholasticism, it was necessary to find a fresh philosophy, in which
entelechy and mechanism might be accommodated side by side.

If one had asked any 'modern' of the seventeenth century to name the
'ancient' doctrine he most abominated, he would most likely have replied,
'Substantial form'. Let us recall what was rejected under this name, and
why.

The medieval account of physical nature had been dominated by what we may
call common-sense biology. Biology, indeed, is the science of the living,
and the medievals were no more inclined than we are to endow all physical
bodies with life. What they did do was to take living bodies as typical,
and to treat other bodies as imperfectly analogous to them. Such an
approach was _a priori_ reasonable enough. For we may be expected to know
best the physical being closest to our own; and we, at any rate, are alive.
Why not argue from the better known to the less known, from the nearer to
the more remote, interpreting other things by the formula of our own being,
and allowing whatever discount is necessary for their degree of unlikeness
to us?

Common-sense biology reasons as follows. In a living body there is a
certain pattern of organized parts, a certain rhythm of successive motions,
and a certain range of characteristic activities. The pattern, the sheer
anatomy, is basic; but it cannot long continue to exist (outside a
refrigerator) without accompanying vital rhythms in heart, respiration and
digestion. Nor do these perform their parts without the intermittent
support of variable but still characteristic activities: dogs not only
breathe and digest, they run about, hunt their food, look for mates, bark
at cats, and so on. The anatomical pattern, the vital rhythm, and the
characteristic acts together express dogginess; they reveal the specific
form of the dog. They _reveal_ it; exactly what the specific form
_consisted in_ was the subject of much medieval speculation. It need not
concern us here.

Taking the form of the species for granted, common-sense biology proceeds
to ask how it comes to be in a given instance, say i