Verbally there is a very general agreement; for both the general run of men and people of superior refinement say that it is [eudaimonia], and identify living well and faring well with being happy; but with regard to what [eudaimonia] is they differ, and the many do not give the same account as the wise. For the former think it is some plain and obvious thing like pleasure, wealth or honour…
— Aristotle, Nichomachean Ethics, Book I. The Human Good (NE I.4, 1095a17)
It is significant that, while being social (in the sense of being accepted) is necessary for survival, it is not what is perceived as what is best for humans.
The ancient philosopher Aristotle had a great deal to say about this along with plenty of good advice on how to study ethics:
The principal idea with which Aristotle begins is that there are differences of opinion about what is best for human beings, and that to profit from ethical inquiry we must resolve this disagreement. He insists that ethics is not a theoretical discipline: we are asking what the good for human beings is not simply because we want to have knowledge, but because we will be better able to achieve our good if we develop a fuller understanding of what it is to flourish. In raising this question—what is the good?—Aristotle is not looking for a list of items that are good. He assumes that such a list can be compiled rather easily; most would agree, for example, that it is good to have friends, to experience pleasure, to be healthy, to be honored, and to have such virtues as courage at least to some degree. The difficult and controversial question arises when we ask whether certain of these goods are more desirable than others. Aristotle’s search for the good is a search for the highest good, and he assumes that the highest good, whatever it turns out to be, has three characteristics: it is desirable for itself, it is not desirable for the sake of some other good, and all other goods are desirable for its sake.
Aristotle thinks everyone will agree that the terms “eudaimonia” (“happiness”) and “eu zên” (“living well”) designate such an end. The Greek term “eudaimon” is composed of two parts: “eu” means “well” and “daimon” means “divinity” or “spirit.” To be eudaimon is therefore to be living in a way that is well-favored by a god. But Aristotle never calls attention to this etymology, and it seems to have little influence on his thinking. He regards “eudaimon” as a mere substitute for eu zên (“living well”). These terms play an evaluative role, and are not simply descriptions of someone’s state of mind.
No one tries to live well for the sake of some further goal; rather, being eudaimon is the highest end, and all subordinate goals—health, wealth, and other such resources—are sought because they promote well-being, not because they are what well-being consists in. But unless we can determine which good or goods happiness consists in, it is of little use to acknowledge that it is the highest end. To resolve this issue, Aristotle asks what the ergon (“function,” “task,” “work”) of a human being is, and argues that it consists in activity of the rational part of the soul in accordance with virtue (1097b22-1098a20). One important component of this argument is expressed in terms of distinctions he makes in his psychological and biological works. The soul is analyzed into a connected series of capacities: the nutritive soul is responsible for growth and reproduction, the locomotive soul for motion, the perceptive soul for perception, and so on. The biological fact Aristotle makes use of is that human beings are the only species that has not only these lower capacities but a rational soul as well. The good of a human being must have something to do with being human; and what sets humanity off from other species, giving us the potential to live a better life, is our capacity to guide ourselves by using reason. If we use reason well, we live well as human beings; or, to be more precise, using reason well over the course of a full life is what happiness consists in. Doing anything well requires virtue or excellence, and therefore living well consists in activities caused by the rational soul in accordance with virtue or excellence.
Aristotle’s conclusion about the nature of happiness is in a sense uniquely his own. No other writer or thinker had said precisely what he says about what it is to live well. But at the same time his view is not too distant from a common idea. As he himself points out, one traditional conception of happiness identifies it with virtue (1098b30-1). Aristotle’s theory should be construed as a refinement of this position. He says, not that happiness is virtue, but that it is virtuous activity. Living well consists in doing something, not just being in a certain state or condition. It consists in those lifelong activities that actualize the virtues of the rational part of the soul.
At the same time, Aristotle makes it clear that in order to be happy one must possess others goods as well—such goods as friends, wealth, and power. And one’s happiness is endangered if one is severely lacking in certain advantages—if, for example, one is extremely ugly, or has lost children or good friends through death (1099a31-b6). But why so? If one’s ultimate end should simply be virtuous activity, then why should it make any difference to one’s happiness whether one has or lacks these other types of good? Aristotle’s reply is that one’s virtuous activity will be to some extent diminished or defective, if one lacks an adequate supply of other goods (1153b17-19). Someone who is friendless, childless, powerless, weak, and ugly will simply not be able to find many opportunities for virtuous activity over a long period of time, and what little he can accomplish will not be of great merit. To some extent, then, living well requires good fortune; happenstance can rob even the most excellent human beings of happiness. Nonetheless, Aristotle insists, the highest good, virtuous activity, is not something that comes to us by chance. Although we must be fortunate enough to have parents and fellow citizens who help us become virtuous, we ourselves share much of the responsibility for acquiring and exercising the virtues.
— Stanford Encyclopedia of Philosophy, http://plato.stanford.edu/entries/aristotle-ethics/#HumGooFunArg