produce death.

Moreover, it is extraordinarily contagious. Every one knows how a hearty
laugh spreads, and how quick the response to a smile. Indeed, emotion
has probably for one of its main functions the producing of an effect
on some one else, and all the world uses emotion for this purpose. Anger
is used to produce fear, sorrow to evoke sympathy, fear is to bring
about relenting, a smile and laughter, friendliness, except where one
smiles or laughs _at_ some one, and then its design is to bring sorrow,
anger, or pain. The leader maintains a hopeful, joyous demeanor so that
his followers may also be joyous or hopeful and thus be energized to
their best. Morale is the state of emotion of a group; it is raised when
joyous, energizing emotions are set working in the group and is lowered
when pessimistic deënergizing emotions become dominant. A city or a
nation becomes energized with good news and success and deënergized when
the battle seems lost.

The spread of emotion from person to person by sympathetic feeling or
the reverse (as when we get depressed because our enemy is happy) is a
social fact of incalculable importance. The problem of the nervous
housewife is a problem of society because she gives her mood over to her
family or else intensely dissatisfies its members so that the home ties
are greatly weakened.

This spread of emotion was happily portrayed by a motion picture I
recently saw. Old Grouchy Moneybags, wealthy beyond measure and
afflicted with gout, is seated at his breakfast table. In the next room,
seen with the all-seeing eye of the movie, the butler makes love to the
very willing maid. In the kitchen the fat cook is feeding the ever
hungry butcher's boy with gingerbread and cake, and on the back steps