body; that somewhere in the interaction of tissues, in the
chemistry of life, arises thought, purpose, emotion, conduct and
deed. But we need not go so far afield as pathology to show this,
for common experience demonstrates it as well.

If character is control of emotions, firmness of purpose,
cheerfulness of outlook and vigor of thought and memory, then the
tired man, worn out by work or a long vigil, is changed in
character. Such a person in the majority of cases is irritable,
showing lack of control and emotion; he slackens in his life's
purposes, loses cheerfulness and outlook and finds it difficult
to concentrate his thoughts or to recall his memories. Though
this change is temporary and disappears with rest, the essential
fact is not altered, namely, fatigue alters character. It is also
true that not all persons show this vulnerability to fatigue in
equal measure. For that matter, neither do they show an equal
liability to infectious diseases, equal reaction to alcohol or
injury. The feeling of vigor which rest gives changes the
expression of personality to a marked degree. It is true that we
are not apt to think of the tired man as changed in character;
yet we must admit on reflection that he has undergone
transformation.

Even a loaded bowel may, as is well known, alter the reaction to
life. Among men who are coarse in their language there is a
salutation more pertinent than elegant that inquires into the
state of the bowels.[1] The famous story of Voltaire and the
Englishman, in which the sage agreed to suicide because life was
not worth living when his digestion was disordered and who broke
his agreement when he purged himself, illustrates how closely