has gone. The timidest one will turn and fight with every sign of
fury. Watch a mother when her young are threatened,--bear, or cat or
lion or human. Fear has no place then. It is entirely displaced by
anger over the balking of the maternal instinct of protection.
Strictly speaking, pugnacity belongs among the instincts neither of
self-preservation nor of race-preservation, but is a special device
for reinforcing both groups.

As fear supplies the energy for running, so anger fits us for
fight,--and for nothing but fight. The mechanism is almost identical
with that of fear. Brain and liver, adrenals and thyroid are the
means, but the emotion presses the button and releases the energy,
stopping all digestion and energizing all combat-muscles. The blood is
flooded with fuel and with substances which, if not used, are harmful
to the body. We were never meant to be angry without fighting. The
habit of self-control has its distinct advantages, but it is hard on
the body, which was patterned before self-control came into fashion.
The wise man, once he is aroused, lets off steam at the woodpile or on
a long, vigorous walk. He probably does not say to himself that he is
a motor animal integrated for fight and that he must get rid of
glycogen and adrenalin and thyroid secretion. He only knows that he
feels better "on the move."

The wiser man does not let himself get angry in the first place unless
the situation calls for fight. However, the fight need not be a
hand-to-hand combat with one's fellow man. William James has pointed
out that there is a "moral equivalent for war," and that the energy of
this instinct may be used to reinforce other impulses and help
overcome obstacles of all sorts. A good deal of the business man's
zest, the engineer's determination, and the reformer's zeal spring