Objectivists -- and sometimes libertarians -- spend a lot of time arguing about the virtue of selfishness.  This confuses some people who do not understand that Rand used the term "selfishness" to shock.  When she spoke of being selfish, she really spoke of rational self-interest.  It's important to remember this, for otherwise a lot of people just won't understand when you tell them that "selfishness" is good.

The key to ethical egoism is that it is a philosophy of rational self-interest.  Both those terms must be present. Take away the "rational," and you're left with amoral hedonism. Take away the "self-interest," and of course you're no longer dealing with egoism of any sort.

I believe that the basis for true benevolence is self-interest, too.  The following is an excerpt from David Kelley's Unrugged Individualism: The Selfish Basis for Benevolence.

...Rand [the founder of Objectivism] rejected the assumption that the interests of rational people conflict in any fundamental sense. The objective values required by our nature, the values that underlie our specific interests, require that we seek peaceful, productive, cooperative relationships with others; that we deal with others by trade, exchanging value for value, rather than by plunder and predation. Trade is a principle of justice... Insofar as benevolence means a commitment to behaving peacefully towards others, respecting their rights and giving them what is due, it is an issue of justice, which is a selfish virtue, not an act of altruism. 

Rand also recognized a role for benevolence in the sense of extending positive help... ...[T]he help we give to people whom we value is not a sacrifice. ...[Giving help to strangers, especially in emergencies, is appropriate] on the basis of 'the generalized respect and good will which one should grant to a human being in the name of the potential value he represents. 

...Going further, Objectivists have argued that altruism is incompatible with genuine benevolence. If self esteem is an objective human need [Objectivists hold that it is], then we cannot see ourselves as means to the needs of others -- we cannot accept the premise that someone else's need is a moral claim on our efforts and resources, overriding the use of those efforts and resources for our own benefit -- without coming to see other people as threats and feeling hostility towards them. 

...Accounts of life under communism provide real-world confirmation of [this] analysis. When self-sacrifice for the common good was installed as the organizing principle of society, individuals became mean, petty, suspicious, hostile...

True benevolence is thus self-interested. It is the morality of altruism that generates low viciousness in human beings. Cruelly ironic is the fact that altruism teaches just the opposite while fostering that which it decries. (Here we are using altruism in the Objectivist sense -- a definition that many complain encompasses more than is meant by the dictionary definition of "altruism.")

"But," some ask, "what of negative actions -- harmful actions -- that are obviously selfish?  How can these be good?"

The answer is that selfishness by itself is not qualification enough to proclaim something virtuous.  A philosophy of rational self-interest, such as Objectivism, requires that one behave rationally  -- that one embrace reason as humanity's only means of knowledge, its only guide to values, its only means of determining appropriate morality. The article on these pages regarding Key Objectivist Concepts includes a write-up on why embracing Reason means one must never initiate physical force. The initiation of force includes fraud and theft and the credible threat of force, as well as actual physical violence.

(Objectivists go on an on about being "rational." To be rational as an Objectivist is to apply reason as thoroughly and constantly as one is able; it is to be as ruthlessly logical and judgmental as one can manage.) 

Any action an ethical egoist takes is indeed self-interested -- but it must also be rational. By Objectivist definition, "good" is that which promotes and sustains the rational life of the individual (and evil is that which works against this goal). But the standard of value for Objectivist ethics is not life at any cost, or survival at any price; it is rational life, which means that death is preferable to acting irrationally. Thus an Objectivist would rather die than live by sacrificing an innocent individual. An Objectivist would choose not to survive rather than initiate force.

(One caveat: preemptive, retaliatory force -- force used in response to the credible threat of force -- is morally justified; this means that it's justified to make the first strike if one reasonably believes one is about to experience initiated force. The credible threat constitutes the initiation even if the threatened action has not yet been taken.)

Some of the Objectivist virtues that go hand in hand with this rationality are productivity, purpose, and self-esteem. They follow logically -- for a rational, self-interested person must...

A) be productive in order to exchange value for value as a free trader, which is central to Objectivist economics -- and indeed to all relationships among ethical egoists; 

B) possess the self-esteem necessary to validate his or her interests, as one's self-interest cannot be achieved if one believes one's interests are not "worthy;"

C) possess a sense of purpose to make productivity worthwhile, for why would one be productive if one believed there was no point to life and to living it?