Many people do not agree with the statement that people are typically concerned only with their own being. So did Socrates in his dialogues described by Plato in Republic.
Within the line of his arguments, connected with this issue, Socrates mainly operated with the definition of “justice”. What is “justice” according Socrates? As we can see in the 4th Book of Republic, justice is when every man does what he must do and can do in the best way, and has what he should have. Using his own, so called Socratic method, he showed his opponents that there are contradictions in their thesis. He also compared between man and state in his arguments. According to Socrates, man as well as the state, should be rational and wise to be successful. To be wise and rational means to be just, as it derives from his dialogue with Thrasymachus in the 1st Book of Plato’s Republic. To be just is reasonable, because injustice is not profitable and leads to impossibility of common action. Common activity is necessary for achieving most of the purposes, especially for the state, so thinking not only about your well being but also about others is not only useful – it is vital for a state and person’s existence. That’s why justice is better than injustice, which can not be successful for a long time.
Talking about his arguments, it should be noticed that they were quite compelling, especially for his time. Socrates’ understanding for justice and necessity for every man to be just is quite rational and persuasive for his interlocutors. Nevertheless, it is worth noted that Glaukon’s remark in the 2nd Book of Plato’s Republic, which talks about justice as a means to prevent any man from being the oppressor, as well as to be oppressed, has a fine amount of sense. Socrates’ comparison of a state and man is quite disputable, maybe not 100% correct, but his thoughts about rational and Divine principle in every human being are still actual.