accustomed to this special change. The current encounters resistance, and in overcoming this resistance it causes the cells to glow. This white-heating of the cells we call consciousness. Consciousness, in short, is probably nerve-glow.
Now we know by experiment that the heat of the hemispheres rises while conscious processes are going on, and does not rise to the same degree when processes of more reflex action are taking place in them. Furthermore, we have reason to think that the molecular action of the cortical cells must be of the same nature as that which takes place in the nerves, since by mere repetition of the action the one develops into something indistinguishable from the other. For at each repetition of any brain action, consciousness of it grows less, till finally we cease to be conscious of it at all; that is to say, the molecular change occurs with ever-increasing ease till at last it comes to be performed quite automatically and quite unconsciously.
Phenomena of both normal and abnormal states of consciousness hint that this theory is correct, as I shall now try to make evident.
