The natural objects that I propose to consider are broadly those
physical objects which are studied and referred to by science
and by a common sense view, informed by science, of the world.
Natural objects are, philosophically speaking, individuals; they
are involved as units in dynamic, causal processes. I shall draw
a distinction between natural objects and the abstract objects
of mathematics, in particular set theory. Natural objects
encompass atoms and molecules; cells and organisms, including
you and me; the objects of everyday life such as chairs and
automobiles; nations, continents, ecosystems, mountain ranges,
geological faults; planets, stars and galaxies. Each natural
object, when regarded internally, is a dynamic system with
various interacting parts and components (some of which may be
natural objects in their own right); when regarded externally, a
natural object acts as a unit with respect to a larger system or
systems (which may again be natural objects) of which the given
object forms a part o