which the forces of the mind, affection and thought, are derived. It is held that the chemical changes going on in the stomach and in the system in general, generate heat and forms of activity, which are communicated to the blood; the blood in turn conveys them to the brain, and the consequent chemical changes and activity in the brain produce affection and thought. It is this erroneous conception that Materialists have in mind in teaching that forces liberated by chemical changes in the brain give rise to emotion. Pursuing the same order of reasoning, Spencer concludes that the "evolution of thought and emotion varies, other things being equal, with the supply of blood to the brain."[1] If this were true, to think prolifically or love intently one need but to invert the body, when the rush of blood to the head would be accompanied by the "evolution of thought and emotion." The fact is that increased affection and thought operative in the mind communicate a correspondingly augmented activity to the brain itself, which thereby consumes more blood-supply in repairing the waste and in building anew to meet the increased force of affection and thought.
- ↑ First Principles, p. 215.
