(1820-1903) held to evolution in human society. Wrote First Principles . The world is a vast evolutionary process of matter, motion, and force. "Matter, Motion, and Force are not themselves ultimate realities, but represent the limits of knowledge" as modes of the unknowable. The redistribution of matter, motion, and force proceeds from the relatively indefinite state of homogeneity to the relatively heterogeneous integration and differentiation of matter. The principle
of evolution applies to all aspects of existence from cosmologyto culture. Knowledge of the source of evolution (the Unknowable) is not forthcoming
( agnosticism )