A lot of people act out of self-interest-- most people act out of self-interest. Strict self-discipline and a solid amount of willpower are key to overcoming indulging yourself. It is survival of the fittest; our survival instinct reincarnate. It is to stoutly defy your very nature to risk your chances in an effort to bolster the chances of another. As a person's well being is both mental and physical, this includes if their actions are a vie for a particular set of feelings or if they are actually dealing with something in a physical sense(i.e. food, shelter etc.) . Many rise to the occasion of devoting yourself entirely to others, but it is a difficult task: you must first of all be able judge all situations soundly and without bias; you have to listen with your ears and not your heart; the most quintessential and thus perhaps the most difficult part is overcoming your innate desire to value your wants and needs above other peoples'; it is this, however, that would be your undoing in your bout to surmount your own "selfishness": the desires of the common man-- of every man-- would have to be just as important to you as they to are to them. You just simply must submit yourself to a higher calling, to a power you thought not had, when it reality it was just that you didn't comprehend how to use it. Balance must be established between what you want, and what they want-- none may surpass the other; all must remain equal.
The next aspect to understanding this subject is best understood by asking and drawing conclusions to two questions: 1.) Is being self-interested a bad thing? And 2.) What constitutes "selfishness?" To answer the first one: no, for the most part. Throughout all of time it is those who were self-interested that pioneered the world and promoted growth. It is capitalistic by nature that people respond to a reward system and other stimulation in that vein. Regarding this, it is by pursuing their self-interests that people are able to put forth such genuine vigor into what they do; it is they who craft the world as they see fit to secure a better future for them, their friends and family, and those like them who have been through such similar hardships. Others run rampant, however, and they abuse the power bestowed on them; the power that was meant to keep all at balance and they shift it all to their end. The error in this is that as the social hierarchy becomes so thusly unbalanced it is soon to collapse and fall in on itself. These tyrants to the core, however, work the magic in a bit of a different way: they push people to such extremes that it creates numerous individuals who have had enough of such oppression and rise to stand against it. Individuals who muster the strength to triumph for the innate desire to secure a safe and comfortable future for those they care about. The second question does not have such a resolute answer. Is it selfish to take what you need and nothing more? Even if someone else needs that stuff too? Would it then be selfish to keep the food to ensure that you and yours have enough to live, or would you be deigned to split the food, even if at a full it was barely enough to feed one family, let alone two at half o it's value. Or is it only selfishness when you begin to take more than you need, and as a result someone is deprived of what they need; that only in the cases where you have a surplus to give away and can still retain enough of what you need to make it through life? Only when these two questions have been considered can one begin to understand as to whether people are self-interested, or more so: if it truly matters; if someone does the right thing, does it matter why they did it, or just that they did it? I'm sure that most of us would be ascertained that the it's better to have good done for the wrong reasons than only mere good intent.