The course of evolution is to a greater integration of similarly functioning ganglia.

The general tendency of evolution is from structure to function, from bondage to freedom of the individual elements.

Psychology is the science of psychic states both as to content and form, regarded from an objective standpoint, and brought in relation to the living corporeal individual.

The tendency of life is not the preservation of the species, but solely the preservation of each individual organism, as long as it is in existence at all, and is able to carry on its life processes.

The principle of recognition of evil under all its guises is at the basis of the true education of man.

Self-preservation is the central aim of all life-activities.

Science is the description of phenomena and the formulation of their relations.