Coming to the answer given by Nikias, we perceive that this deficiency is in a certain manner supplied. Courage is said to consist in knowledge: in knowledge of things terrible, and things not terrible. When Lachês applies his cross-examination to the answer, the manner in which Nikias defends it puts us upon a distinction often brought to view, though not always adhered to, in the Platonic writings. There can be no doubt that death, distemper, loss of wealth, defeat, &c. are terrible things (_i.e._ the prospect of them inspires fear) in the estimation of mankind generally. Correct foresight of such contingencies, and of the antecedents tending to produce or avert them, is possessed by the physician and other professional persons: who would therefore, it should seem, possess the knowledge of things terrible and not terrible. But Nikias denies this. He does not admit that the contingencies here enumerated are, always or necessarily, proper objects of fear. In some cases, he contends, they are the least of two evils. Before you can be said to possess the knowledge of things terrible and not terrible, you must be able to take correct measure not only of the intervening antecedents or means, but also of the end itself as compared with other alternative ends: whether, in each particular case, it be the end most to be feared, or the real evil under the given circumstances. The professional man can do the former, but he cannot do the latter. He advises as to means, and executes: but he assumes his own one end as an indisputable datum. The physician seeks to cure his patient, without ever enquiring whether it may not be a less evil for such patient to die than to survive. [Side-note: Postulate of a Science of Ends, or Teleology, dimly indicated by Plato. The Unknown Wise Man--correlates with the undiscovered Science of Ends.]