ese each take some particular portion of
the universe for their study, philosophy does not specialize in this
way, but deals with the universe as a whole. The universe is one, and
ideal knowledge of it would be one; but the principles of
specialization and division of {3} labour apply here as elsewhere, and
so astronomy takes for its subject that portion of the universe which
we call the heavenly bodies, botany specializes in plant life,
psychology in the facts of the mind, and so on. But philosophy does
not deal with this or that particular sphere of being, but with being
as such. It seeks to see the universe as a single co-ordinated system
of things. It might be described as the science of things in general.
The world in its most universal aspects is its subject. All sciences
tend to generalize, to reduce multitudes of particular facts to single
general laws. Philosophy carries this process to its highest limit. It
generalizes to the utmost. It seeks to view the entire universe in the
light of the fewest possible general principles, in the light, if
possible, of a single ultimate principle.

It is a consequence of this that the special sciences take their
subject matter, and much of their contents, for granted, whereas
philosophy seeks to trace everything back to its ultimate grounds. It
may be thought that this description of the sciences is incorrect. Is
not the essential maxim of modern science to assume nothing, to take
nothing for granted, to assert nothing without demonstration, to prove
all? This is no doubt true within certain limits, but beyond those
limits it does not hold good. All the sciences take quite for granted
certain principles and facts which are, for them, ultimate. To
investigate these is the portion of the philosopher, and philosophy
thus takes up the thread of knowledge where the sciences drop it. It
begins where they end. It investigates what they take as a matter of
course.

Let us consider some examples of this. The science of geometry deals
with the laws of space. But it takes {4} space just as it finds it in
common experience. It takes space for granted. No geometrician asks
what space is. This, then, will be a problem for philosophy. Moreover,
geometry is founded upon certain fundamental propositions which, it
asserts, being self-evident, require no investigation. These are
called "axioms." That two straight lines cannot enclose a space, and
that equals being added to equals the results