It may be objected that in science a part is not the total science.
Doubtless, the notion which is actualized, and which is studied to
the exclusion of others, because there is special need of it, is
only partially an actualization. Nevertheless, in a latent manner it
potentially comprises all the other notions it implies. Thus, all the
notions are contained in each part of the science, and in this respect
each part is the total science; for what is only partially actualized
(potentially) comprises all the notions of science. Each notion that
one wishes to render explicit is at one's disposition; and this in
every part of the science that is considered; but if it be compared
with the whole science, it seems to be there only potentially. It
must not, however, be thought that the particular notion does not
contain anything of the other notions; in this case, there would
be nothing systematic or scientific about it; it would be nothing
more than a sterile conception. Being a really scientific notion, it
potentially contains all the notions of the science; and the genuine
scientist knows how to discover all its notions in a single one, and
how to develop its consequences. The geometrical expert shows in his
demonstrations how each theorem contains all the preceding ones, to
which he harks back by analysis, and how each theorem leads to all the
following ones, by deduction.