"It keeps his adversary in ignorance of the effect produced by his reasoning and allows him to take his chance, until the moment when, in spite of this feigned indifference, he reveals himself and permits his mind to be seen.
"Now, to know the designs of a rival, when he is ignorant of those that we have conceived, is one of the essential factors of success.
"In every way, he who is informed about the projects of his adversary walks preceded by a torch of light, while the adversary, if he can not divine his opponent's plans, continues to fight in darkness."
The most elementary common sense counsels then cool-headedness when exchanging ideas, even when the discussion is of quite an amicable nature.
From this habit there will result a very praiseworthy propensity to exercise self-control, which is only a sort of superior cool-headedness.
It is also the cause of a noble pride, because it is more difficult to win a victory over one's passions than to conquer ordinary enemies, and he who, with the support of common sense, succeeds in ruling himself, can calculate, without arrogance, the hour when he will reign over the minds of others.
LESSON XII
COMMON SENSE DOES NOT EXCLUDE GREAT ASPIRATIONS
"A very common error," says Yoritomo, "is that which consists in classifying common sense among the amorphous virtues, only applicable to things and to people whose fundamental principle is materiality.
"This is a calumny which is spread broadcast by fools who scatter their lives to the four winds of caprice and extravagance.