The psychical function of humor is to delicately cut the
surface tension of consciousness and disarrange its structure
that it may begin again from a new and strengthened base. It
permits our mental forces to reform under cover, as it were,
while the battle is still on. Then, too, it clarifies the
field and reveals the strategetic points, or, to change the
figure, it pulls off the mask and exposes the real man. No
stimulus, perhaps more mercifully and effectually breaks the
surface tension of consciousness, thereby conditioning the
mind for a stronger forward movement, than that of humor. It
is the one universal dispensary for human kind: a medicine for
the poor, a tonic for the rich, a recreation for the fatigued
and a beneficient check to the strenuous. It acts as a shield
to the reformer, as an entering wedge to the recluse and as a
decoy for barter and trade.

Humor is as necessary to our mental and spiritual life as are vitamins
to our physical well-being. Ruskin has called our attention to the
tendency of rivers to lean a little to one side, to have "One shingly
shore upon which they can be shallow and foolish and childlike, and
another steep shore under which they can pause and purify themselves
and get their strength of waves fully together for due occasions," and
has likened them to great men who must have one side of their life
for work and another for play. Action and reaction must be balanced:
seriousness and lightness. "Men who work prodigously must play with
equal energy," says one commentator. "Humor is the gift of the deeply
serious man," remarks another. "There have been very few solemn men,
but their solemnity was evidence, not of their gifts, but of their
defects; as a rule greatness is accompanied by the overflow of the