as the basis and the limits of their explanation, is precisely and
peculiarly the problem of philosophy, which may therefore be said to begin
where science ends. It cannot be founded upon demonstrations, for they
lead from known principles to unknown, but everything is equally unknown
and external to philosophy. There can be no principle in consequence of
which the world with all its phenomena first came into existence, and
therefore it is not possible to construct, as Spinoza wished, a philosophy
which demonstrates _ex firmis principiis_. Philosophy is the most general
rational knowledge, the first principles of which cannot therefore be
derived from another principle still more general. The principle of
contradiction establishes merely the agreement of concepts, but does not
itself produce concepts. The principle of sufficient reason explains the
connections of phenomena, but not the phenomena themselves; therefore
philosophy cannot proceed upon these principles to seek a _causa
efficiens_ or a _causa finalis_ of the whole world. My philosophy, at
least, does not by any means seek to know _whence_ or _wherefore_ the
world exists, but merely _what_ the world is. But the _why_ is here
subordinated to the _what_, for it already belongs to the world, as it
arises and has meaning and validity only through the form of its
phenomena, the principle of sufficient reason. We might indeed say that
every one knows what the world is without help, for he is himself that
subject of knowledge of which the world is the idea; and so far this would
be true. But that knowledge is empirical, is in the concrete; the task of
philosophy is to reproduce this in the abstract to raise to permanent
rational knowledge the successive changing perceptions, and in general,
all that is contained under the wide concept of feeling and merely
negatively defined as not abstract, distinct, rational knowledge. It must
therefore consist of a statement in the abstract, of the nature of the
whole world, of the whole, and of all the parts. In order then that it may
not lose itself in the endless multitude of particular judgments, it must
make use of abstraction and think everything individual in the universal,
and its differences also in the universal. It must therefore partly
separate and partly unite, in order to present to rational knowledge the
whole manifold of the world generally, according to its nature,
comprehended in a few abstract concepts. Through these concepts, in which
it fixes the nature of the world, the whole individual must be known as
well as the universal, the knowledge of both therefore must be bound
together to the minutest point. Therefore the capacity for philosophy
consists just in that in which Plato placed it, the knowledge of the one
in the many, and the many in the one. Philosophy will therefore be a
sum-total of general judgments, whose ground of knowledge is immediately
the world itself in its entirety, without excepting anything; thus all