he cannot do, he avoids the danger of falling into errors, and of seeing himself miserable.  By knowing himself, he knows likewise how to judge of others, and to make use of their services for his own advantage, either to procure himself some good, or to protect himself from some misfortune; but he who knows not himself, and is mistaken in the opinion he has of his own abilities, mistakes likewise in the knowledge of others, and in the conduct of his own affairs.  He is ignorant of what is necessary for him, he knows not what he undertakes, nor comprehends the means he makes use of, and this is the reason that success never attends his enterprises, and that he always falls into misfortunes.  But the man who sees clear into his own designs generally obtains the end he proposes to himself, and at the same time gains reputation and honour.  For this reason, even his equals are well pleased to follow his advices; and they whose affairs are in disorder implore his assistance, and throw themselves into his hands, depending upon his prudence to retrieve their affairs, and to restore them to their former good condition.  But he who undertakes he knows not what, generally makes an ill choice, and succeeds yet worse; and the present damage is not the only punishment he undergoes for his temerity.  He is disgraced for ever; all men laugh at him, all men despise and speak ill of him.  Consider likewise what happens to Republics who mistake their own strength, and declare war against States more powerful than themselves; some are utterly ruined, others lose their liberty, and are compelled to receive laws from the conquerors.”

“I am fully satisfied,” said Euthydemus, “that a great deal depends on the knowledge of oneself.  I hope you will now tell me by what a man must begin to examine himself.”  “You know,” said Socrates, “what things are good and what are bad?” “Indeed,” answered Euthydemus, “if I knew not that, I were the most ignorant of all men.”  “Then tell me your thoughts of this matter,” said Socrates.  “First,” said Euthydemus, “I hold that health is a good and sickness an evil, and that whatever contributes to either of them partakes of the same qualities.  Thus nourishment and the exercises that keep the body in health are very good; and, on the contrary, those that cause diseases are hurtful.”  “But would it not be better to say,” replied Socrates, “that health and sickness are both good when they are the causes of any good, and that they are both bad when they are the causes of any ill?” “And when can it ever happen,” said Euthydemus, “that health is the cause of any ill, and sickness the cause of any good?” “This may happen,” answered Socrates, “when troops are raised for any enterprise that proves fatal; when men are embarked who are destined to perish at sea; for men who are in health may be involved in these misfortunes, when they who, by reason of their infirmities, are left at home, will be exempted from the mischiefs in which