The truth is that the mistrust of theory arises from a misconception of what it is that theory claims to do. It does not pretend to give the power of conduct in the field; it claims no more than to increase the effective power of conduct. Its main practical value is that it can assist a capable man to acquire a broad outlook whereby he may be the surer his plan shall cover all the ground, and whereby he may with greater rapidity and certainty seize all the factors of a sudden situation. The greatest of the theorists himself puts the matter quite frankly. Of theoretical study he says, "It should educate the mind of the man who is to lead in war, or rather guide him to self-education, but it should not accompany him on the field of battle." Its practical utility, however, is not by any means confined to its effects upon the powers of a leader. It is not enough that a leader should have the ability to decide rightly; his subordinates must seize at once the full meaning of his decision and be able to express it with certainty in well-adjusted action. For this every man concerned must have been trained to think in the same plane; the chief's order must awake in every brain the same process of thought; his words must have the same meaning for all. If a theory of tactics had existed in 1780, and if Captain Carkett had had a sound training in such a theory, he could not possibly have misunderstood Rodney's signal. As it was, the real intention of the signal was obscure, and Rodney's neglect to explain the tactical device it indicated robbed his country of a victory at an hour of the direst need. There had been no previous theoretical training to supply the omission, and Rodney's fine conception was unintelligible to anybody but himself.