In order to understand the existence of physical and mental things,
even of divine things, we need to treat them as actually existing. They cannot be
merely concepts, hypotheses, forms, or information. We may describe some of them
by mathematics but actual things are not constituted by mathematics. This amounts
to taking an Aristotelian view of reality, wherein every real thing is some kind
of substance and has powers for change. This can immediately be contrasted with
an extreme Platonic view, wherein only ideal forms are real, and things in our world
are merely some kind of image or shadow of those ideal forms.
Following Aristotle, we can analyze the nature of individual things. We see how
they all have some form and are all composed of some
matter (Greek hyle). I am going to say that objects all have some
form, and that form is a form of some underlying substance or stuff.4.1By
the term ‘form’, I refer not just to the external shape of an object, but to all
the internal structure and descriptive details necessary to make a full account
of what actually exists at a given moment. Spatial structures are forms, and so
also are any other structures needed, whether they are spatial or not.4.2This
use of the term ‘form’ refers only to static or categorical properties that can
be attributed at any one time. It therefore excludes causal principles since these
describe what might happen at later times.4.3The
form and substance of each thing can be intellectually distinguished, but they never
exist apart in reality. It is never the case that the form of a thing is here and
the substance of it is over there.
This is to adopt a realism that takes seriously the need for substance and also
for changes and processes involving substantial objects. Each object cannot merely
exist self-sufficiently but must be closely linked to others by causes and/or effects.
We therefore need a serious account of how causes exist and operate and how the
causal powers of objects are related to their substantial nature. Because science
is continually discovering new kinds of causes and new ways of causation, the realism
here is not a naive realism wherein we take as real just what appears to our senses.
There are enormously many things and causes that science postulates that are not
apparent to our senses but are inferred from empirical or theoretical considerations.
The present realism, because it stresses the leading role of causes and powers
in generating new processes, is going to be called ‘generative realism.’ If we want
a slogan, we could say “No process without structure, no structure without substance,
no substance without power, no power without process."