Ethical egoism is a theory of ethics which states that all people should act in accordance with their own personal interest. The greatest good is that which is in the best interest of a particular person in the long run. For the duration of this essay, "egoism" and "ethical egoism" will refer to the above definition, and "altruism" will refer to the opinion that one should always act in a way that will benefit others.
There are, according to Rachel, three main arguments in favor of ethical egoism. We will examine them one by one.
The first is an argument containing three parts. (1) It is difficult to know for sure what exactly another person needs; by helping, we might do more harm than good. (2) Each individual is best charged with seeking and fulfilling his own needs; for him to help others would be an intrusion into another's private life, in other words, "Minding another's business." And (3), many people don't appreciate charity. Robert Heinlein, in the novel "Stranger in a Strange Land," expresses this sentiment perfectly. "The Japanese have five ways to say 'thank you"--and every one translates as resentment, in various degrees. Would that English had the same built-in honesty!" In Rachel's words, offering another charity implies to that person that they are unable to care for themselves and require assistance. This implied statement does tend to evoke just as much resentment as saying it outright would. .
It certainly seems logical that each person is best equipped to fulfill his own needs. I am the only person in the world who can know my deepest desires and dreams, so it follows logically that I am the only person in the world who can fulfill my deepest desires and dreams. Any attempt by others to do this would inevitably require a bit of guesswork on their part. Take for example the custom of giving gifts during the holidays. I have a relative who, when asked what she"d like as a present, will only respond with "I don't know, surprise me.