Biology Reference
In-Depth Information
form. There are therefore, in all, four causes which are almost indis-
sociably grouped two by two: the final and formal causes direct the
process, the material and efficient causes carry them out in concrete
terms. At the heart of this Aristotelian concept is the postulate that
matter is not capable of organising itself and to do so it needs a
form which is the equivalent of a mould or a template to guide the
material processes. The form is also the specific essence of a being
in this ontology. It is what it really is without all the little acci-
dents which affect it and which differentiate it from other beings
belonging to the same species. For example, if we want to under-
stand what a human really is, he must be defined by the essence
common to all individual humans, that is to say by all the specific
characteristics corresponding to the human species, leaving aside all
the small individual differences (big, small, blond, brown, etc.)
which are only accidental. In this hylemorphic ontology, explana-
tion by material and efficient (mechanical) processes only has any
sense because they are controlled by the form which is itself subject
to the final cause. The latter is the end of the process when the
form has been produced. If we were to remain with mechanical
causes we would be trapped in an infinite succession of causes and
effects. In contrast, Aristotle's world is a world of finished processes
and this finiteness allows the origin of things to be understood: the
ultimate origin of the statue is also the idea of it in the sculptor's
mind. This applies to everything that exists. Nature therefore has
a plan.
We shall see how this general conception applies to biology.
Aristotle worked on the questions which preoccupy us particularly
in his treatise
The Generation of Animals
, in which he completely
refuted Hippocrates' theory. After setting out the arguments in
his favour, he demolished them one by one. We shall concentrate
on the one which is most important for putting his conception into
context and considering the problems that we are discussing in
this topic.
The resemblance between parents and children concerns general
characteristics such as height or corpulence, as well as parts of the
body such as the head or the feet. Aristotle pointed out that
