CHAPTER V.
THE CONNECTION OF BODY WITH MIND--PHYSIOLOGICAL PSYCHOLOGY--MENTAL DISEASES.
In the foregoing pages we have had intimations of some of the important questions which arise about the connection of mind with body.

The avenues of the senses are the normal approaches to the mind through the body; and, taking advantage of this, experiments are made upon the senses.

This gives rise to Experimental Psychology, to which the chapter after this is devoted.

Besides this, however, we find the general fact that a normal body must in all cases be present with a normal mind, and this makes it possible to arrange so to manipulate the body that changes may be produced in the mind in other ways than through the regular channels of sense.

For example, we influence the mind when we drink too much tea or coffee, not to mention the greater changes of the same kind which are produced in the mind of the drinker of too much alcohol or other poisonous substances.