That we may rightly appreciate what this Monism is, let us now, from a
philosophico-historical point of view cast a comprehensive glance over
the development in time of man's knowledge of nature. A long series of
varied conceptions and stages of human culture here passes before our
mental vision. At the lowest stage, the rude--we may say animal--phase of
prehistoric primitive man, is the "ape-man," who, in the course of the
tertiary period, has only to a limited degree raised himself above his
immediate pithecoid ancestors, the anthropoid apes. Next come successive
stages of the lowest and simplest kind of culture, such as only the
rudest of still existing primitive peoples enable us in some measure to
conceive. These "savages" are succeeded by peoples of a low civilisation,
and from these again, by a long series of intermediate steps, we rise
little by little to the more highly civilised nations. To these alone--of
the twelve races of mankind only to the Mediterranean and Mongolian--are
we indebted for what is usually called "universal history." This last,
extending over somewhat less than six thousand years, represents a period
of infinitesimal duration in the long millions of years of the organic
world's development.

Neither of the primitive men we have spoken of, nor of those who
immediately succeeded them, can we rightly predicate any knowledge of
nature. The rude primitive child of nature at this lowest stage of
development is as yet far from being the restless _Ursachenthier_
(cause-seeking animal) of Lichtenberg; his demand for causes has not yet
risen above that of apes and dogs; his curiosity has not yet mounted to
pure desire of knowledge. If we must speak of "reason" in connection with
pithecoid primitive man, it can only be in the same sense as that in
which we use the expression with reference to those other most highly
developed Mammals, and the same remark holds true of the first beginnings
of religion.[3]