th
that the human understanding is capable of relative knowledge only or of a
knowledge of the relative (Relativity). Nevertheless, according to Spencer,
it is too much to conclude with the thinkers just mentioned, that the
idea of the absolute is a mere expression for inconceivability, and its
existence problematical. The nature of the absolute is unknowable, but
not the existence of a basis for the relative and phenomenal. The
considerations which speak in favor of the relativity of knowledge and its
limitation to phenomena, argue also the existence of a non-relative, whose
phenomenon the relative is; the idea of the relative and the phenomenal
posits _eo ipso_ the existence of the absolute as its correlative, which
manifests itself in phenomena. We have at least an indefinite, though not
a definite, consciousness of the Unknowable as the Unknown Cause, the
Universal Power, and on this is founded our ineradicable belief in
objective reality.

All knowledge is limited to the relative, and consists in increasing
generalization: the apex of this pyramid is formed by philosophy. Common
knowledge is un-unified knowledge; science is partially unified knowledge;
philosophy, which combines the highest generalizations of the sciences into
a supreme one, is completely unified knowledge. The data of philosophy
are--besides an Unknowable Power--the existence of knowable likenesses and
differences among its manifestations, and a resulting segregation of the
manifestations into those of subject and object. Further, derivative data
are space (relations of coexistence), time (relations of irreversible
sequence), matter (coexistent positions that offer resistance), motion
(which involves space, time, and matter), and force, the ultimate of
ultimates, on which all others depend, and from our primordial experiences
of which all the other modes of consciousness are derivable. Similarly the
ultimate primary truth is the _persistence of force_, from which, besides
the indestructibility of matter and the continuity of (actual or potential)
motion, still further truths may be deduced: the persistence of relations
among forces or the uniformity of law, the transformation and equivalence
of (mental and social as well as of physical) forces, the law of the
direction of motion (along the line of least resistance, or the line of
greatest traction, or their resultant), and the unceasing rhythm of
motion. Beyond these analytic truths, however, philo