There is no question here of higher psychic action.

We therefore return to our first definition of Mind, as 'the sum of psychic action in us, whether conscious or unconscious.'

The central nervous system or central marrow (medulla centralis) is the real organ of psychic action in the narrower sense.

Physiologists may say that it is only a question of a peculiar physico-chemical phenomenon, and not a psychic action; but the two cannot be separated.

''All these things present themselves to us as indicating not physiological operations of one brain acting on another, but psychic actions of spirit upon spirit.