The restriction of studies of human intellect and character to studies of conscious states was not without influence on a scientific studies of animal psychology.
Just as the science and art of agriculture depend upon chemistry and botany, so the art of education depends upon physiology and psychology.
Psychology helps to measure the probability that an aim is attainable.
It will, of course, be understood that directly or indirectly, soon or late, every advance in the sciences of human nature will contribute to our success in controlling human nature and changing it to the advantage of the common weal.
There is no reasoning, no process of inference or comparison; there is no thinking about things, no putting two and two together; there are no ideas - the animal does not think of the box or of the food or of the act he is to perform.