Aristotle's discussion of eudaimonia in general is contained in Book 1 of the Nicomachean Ethics. His discussion of the highest form of eudaimonia that displays the most superior characteristic human excellence is in Book 10.
For Aristotle eudaimonia (translated as ‘happiness’ here but see the end of this piece) is summarized as ‘(An) ACTIVITY (energeia) of a being with PSYCHE, (an) activity that engages and displays that being's characteristic EXCELLENCE’ (arete). (This is an interpretation of Aristotle's words rather than a strict translation.) A human being (called for short ‘man’ here, and it is certain that Aristotle was writing about and for men) is a being with a psyche, the only being with all the functions and capacities of psyche, especially the cognitive and moral ones. (Note though that the Greeks, including Aristotle, credited non-human animals with psyche and arete and objects with arete.) But happiness is found only in man, and the forms of excellence constitutive of happiness are confined to cognitive and moral activity and are not extended to characteristic human activity in general and the excellence thereof.
Aristotle says that there is a highest good for man (a datum of Greek ethics and perhaps of popular thought too). If there is a plurality of goods, then they cannot all be of equal standing and one of them must be the highest good.
The highest good for man must be eudaimonia. Happiness is self-sufficient (one does not need anything else) and is an END (telos) in itself, not a means to a further or higher end. Therefore, there cannot be a higher good for man. Every action has a single and the same ultimate end, and this is happiness, since happiness is not sought for the sake of other things and all other things are sought for the sake of happiness. There must be such an end, or every action would be performed for the sake of some further end and there would be an infinite series of means and ends. Eudaimonia is the only good that meets all these requirements for a highest good.
According to Aristotle, eudaimonia is activity that engages and displays excellence that is characteristic of a human being. The greatest happiness is achieved by the man who performs the activity that displays the greatest excellence characteristic of a human being.
What is the activity that displays the greatest excellence characteristic of a human being? It is an activity that a human being alone performs or a human being better than anything else performs. What a thing or person alone does or does better than anything else is its/his FUNCTION (ergon). So, cutting is the function of a knife, and the excellence of a knife consists in its cutting well, or the quality that enables it to do this, i.e. sharpness. Making shoes is the function of a cobbler, and the excellence of a cobbler consists in his making shoes well, or whatever quality or set of qualities enable him to do this (they constitute his TECHNE, specialized knowledge/skill, expertise).
A human being, qua human being, has a function too, and the excellence of a human being consists in his performing this function well, or the quality/qualities that enable him to do this. What is this function? What does a man alone or a man better than anything else do? The good man is the man who is good at being a man, as the good cobbler is the cobbler who is good at being a cobbler.
A cobbler is a man who makes shoes. What is the equivalent distinctive activity of a man? It is to be found in a human being's ability to reason and his capacity for moral action, or rather the exercise or realization of these capacities. A good man is a man who reasons well and behaves well morally. The best man is the man who performs the highest form of reasoning best. The highest form of reasoning, theoria (‘CONTEMPLATION’), displays a higher form of excellence than moral excellence, in fact the highest form of excellence. The greatest happiness is enjoyed by such a man. He is displaying the highest form of characteristic human excellence, and this is happiness and living well, in fact living in the best possible way.
So what is wrong with this account of happiness?
Does energeia mean activity generally or a specific activity? Aristotle does not think that happiness is any activity, even any activity that manifests characteristic human excellence. He does however recognize more than one form and level of happiness and these seem to correspond to different forms of energeia, to different activities manifesting different excellences. So presumably it does not refer to activity tout court or to one particular activity only.
But whether energeia is to be understood as activity or an activity/activities, happiness itself does not seem to be an activity of any kind, however satisfying or fulfilling the activity may be, but rather a state or condition of one's life conjoined with the way it is experienced and regarded by the happy individual, i.e. it has both an objective and subjective element. Activities may be constituents of happiness, but (an) activity itself cannot be happiness. Aristotle is simply guilty of a ‘category mistake’. He has placed happiness in the wrong category, as it is not the same sort of thing as an activity. It is not something you do. Also, activity alone cannot constitute happiness; there are surely other constituents to be accounted for, objective and subjective.
On the other hand, ‘activity’ may not be an accurate translation of Aristotle's word energeia. Aristotle says that the energeia that is the highest good is theoria. Whatever this is exactly, Aristotle surely did not think of it as an activity in our sense of the word ‘activity’. The word energeia here means the realization or actualization, the ‘active exercise’ (Rackham) of a capacity or potentiality (dunamis), X-ing as opposed to being able to X. (It is ironic that the word ‘energy’ denotes a dunamis and not an energeia.) Understood in this way, what Aristotle says makes more sense: eudaimonia is the realization of a capacity of a being with a psyche that displays characteristic human excellence. And theoria seems to be more of a state, which is what happiness (though maybe not eudaimonia) is. Perhaps Aristotle is not guilty of a category mistake after all; rather we are in thinking that energeia is something it isn't.
It seems to be a very elitist, perfectibilist and intellectualist account of what happiness is, with its exclusive focus on excellence, intellectual or moral. Joe Bloggs cannot expect much happiness from it. This seems counter-intuitive. It also comes across as smug and self-congratulatory. Aristotle cannot have been unaware that his picture of the supremely happy man was a self-portrait, that there were few other exemplars, and not many more who aspired to the secondary happiness of moral excellence as measured by his exacting standards and requirements.
It seems to be a very narrow view of what constitutes happiness, though Aristotle does insist that a happy life must contain other ingredients, e.g. pleasure, friendship. But these are ingredients in the life of a man of intellectual or moral excellence only, not in the life of your ordinary Joe; and there is no recognition of a variety of combinations of goods as constitutive of happiness. The idea too that happiness may be a fortuitous thing for which no specific combination of goods can be prescribed for any particular individual is not to be found in Aristotle.
It is not true that all our activities have a single end, and the same ultimate end. Surely, they have a multiplicity of unrelated ends, and there is no single architectonic end of them all. Even if it is true (it is not true: there are activities that are undertaken either as means to ends or as ends in themselves, as Aristotle acknowledges) that every activity is directed towards an end, it is not true that there is an end towards which every activity is directed. That every line ends somewhere does not entail that there is somewhere that every line ends. That everybody loves somebody does not entail that there is somebody who is loved by everybody.
It is questionable whether happiness is an end at all, for the sake of which and towards the achievement of which we employ means in the form of goods. This confuses constituents of happiness with means to happiness. It also assumes that happiness is able to be achieved by having it as an end of action, as other things are achieved as ends of action. This is not how we come by happiness. Happiness is not a good that is achieved as other goods are, by pursuing them. Happiness is a supervenient good, unsought (except as what philosophers call an ‘intentional object’) and unforeseen. One cannot imagine Aristotle's happy man being ‘surprised by joy’.
Does a human being, qua human being, have a specifiable function or functions? What is wrong with the analogies that underlie Aristotle's argument? The function of a cobbler, making shoes, is a specialized skill (techne). Not everyone possesses it. What is the specialized skill that is the function of a man? Is it something that all men possess, or only some men, like making shoes? If the former, how can it be specialized? If the latter, what is the function of those who lack this specialized skill? A different specialized skill? But then the same objections apply. Also, even if human beings have a function, why single out reasoning and moral action as the activities that human beings alone or better than other things perform? There are plenty of other things that only human beings do, e.g. sport, creative and performing arts, applied sciences. Why should happiness not be regarded as excellence in the performance of these peculiarly human activities? Presumably these would count as lower level activities that deploy inferior forms of excellence, if any at all. In any case one feels that human happiness is not to be identified with performing a function, well or badly, assuming that there is such a function; that it is not a kind of expertise or form of excellence; that a happy man is not some kind of expert at being a man. But if you think that happiness is doing something well, including doing well morally, you might not think these notions outlandish. Surely doing something well entails knowing how to do it? If it is difficult and not everyone can do it, does it not entail techne of some kind? Aristotle was not alone in thinking like this. It is a constant in Plato's moral thinking, who got it from Socrates, who was probably applying to moral conduct a commonly held notion of what is involved in being able to do something well.
There is no mention of the subjective, psychological, phenomenological element (the ‘what it is like to be’) of happiness; of how happiness as a state is experienced; of the internalization of the objective state of his life that constitutes his happiness. Without the experience of happiness (not necessarily identified or recognized as such) there is no happiness.
Of the two forms of excellence that Aristotle identifies as characteristic of human excellence and believes to be different levels of happiness, he does not give a convincing argument as to why one displays greater excellence than the other and constitutes a higher level of happiness. Perhaps Aristotle thought that people possessed of moral excellence may not all be capable of the highest levels of intellectual excellence (in fact he did think this), but not vice versa, so that intellectual trumps moral excellence.
Happiness seems to belong only to adult and mature people who have acquired the necessary excellences, especially moral excellence, over a considerable stretch of time. It is something you have to serve your time to rather than something that happens to you at any age. And surely to say that a man is happy is not to make a comment on the whole of his life, even though happiness is an epiphenomenon of a complex of goods and something stable and of some fixity and duration, not fleeting and transitory like pleasure.
The analysis of the concept of happiness may be a proper thing for a philosopher to undertake, but why is it a proper subject for ethics or moral philosophy? Is there something inherently ethical or moral (not to say political as well, according to Aristotle) in the notion of happiness? There is of course in Aristotle's notion of it, but is he right to understand it in this way? If, thanks largely to Greek philosophers beginning with Socrates, happiness had not been more or less appropriated by moral philosophy, what other branch of the subject today do we think would be more appropriate to handle it? Would we still think it should be ethics/moral philosophy? Why/why not?
Aristotle may be engaged in Ethics (he gave the subject its name) even in meta-ethics, but is he engaged in moral philosophy? Related to the previous point is the point that Aristotle's project is open to the same kind of criticism as the central argument in Plato's Republic. This is that doing the right thing because it will be good for me – being just or living in a way that most engages certain peculiarly human capacities – is not a moral argument at all, but rather a prudential one since it is a self-regarding argument. (Technically it is called ‘eudaimonistic egoism’.) A moral argument should surely be grounded on the interests of others. Socrates and Plato believed that doing good to others was also good for oneself – or rather the opposite, that doing wrong to others wronged oneself. But this belief is compatible with the belief that one should do good to others because it is a means of doing good to oneself, and it this belief that comes across more strongly. The moral versus prudential distinction is akin to the altruism versus egoism distinction. It is a case of either/or not of both/and. Seeking the good of others while at the same time also seeking one's own good is not altruism (though seeking the good of others may be egoism if it is the means to the end of one's own good). But if Plato and Aristotle are guilty of this, so is just about every other Greek philosopher who wrote about ethics. Who singles out the good of others as the main reason for living the good life? Nobody thinks to ask ‘cui bono?’ where the summum bonum is concerned. It is assumed to be one's own good and telling people what they most want to know – what is best for them – is a preoccupation of Greek ethical theory. Much of ancient Greek moral philosophy has little to do with morality as we understand it, and much to do with perfectibilism as self-interest. Aristotle is hailed as the founder of Virtue Ethics, but the virtues play rather a different role in his arguments from the role they play in modern theories.
Aristotle does have a lot to say about moral excellence, though this is better thought of as excellence of character (ethike arete) rather than moral excellence. But many of the particular excellences of character are self-regarding rather than other-regarding ones, or only incidentally and indirectly the latter, and are to be developed and exercised ultimately to serve one's own interest, one's own happiness. Their incidental other-regarding function is a not unimportant one, even if incidental, in the context of the relatively small community of a Greek polis. But there is little or no mention in the discussion of excellence of character of the duties one owes to others, and the rights that should be accorded to them as fellow persons on deontological rather than teleological or consequentialist grounds
I think that there is a conceptual mismatch between eudaimonia and ‘happiness’. I don't think that eudaimonia meant to Aristotle what ‘happiness’ means to us. When he introduces the term, he uses eudaimonia as a synonym for ‘doing/faring well’ (to eu prattein) and for ‘living well’ (to eu zen). I don't think there is an English word or expression for eudaimonia or a Greek word for ‘happiness’: we inhabit different concept worlds. This makes it difficult to give a critical account of the one in terms of the other, and very difficult to do justice to and to be fair to Aristotle's account. We should be asking how well Aristotle handles eudaimonia and related Greek concepts, rather than how well he deals with concepts that are part of our concept world, not his, unless we can be sure that both Greek and English terms denote the same concepts and the same referents, where such exist.
I think the closest approximation to eudaimonia may be ‘success in life’ (and the Greeks seem to have thought that you could not have worldly success unless a divine power (daimon) was well (eu) disposed to you), and that what Aristotle is doing is telling us what this consists of – essentially to ‘be the best you can be’, in the words of that awful-sounding injunction. Success in life was certainly highly prized by the Greeks, especially of Aristotle's social class; but not many of them would have thought that it was either intellectual or moral excellence or the kinds of self-improvement Aristotle commends. Success in life was essentially what other people envied you for – wealth, power, social status and social approval – and wanted for themselves (so nothing has changed there then). They would surely have found Aristotle's account perplexing and repellent, just the sort of high-minded, unworldly, irrelevant stuff, removed from all the practical purposes of real life, you might expect from a philosopher, in spite of Aristotle's avowed purpose to enable men actually to become ‘good’ (agathoi – another problematical word) men, not just to understand what it means to be a good man. But Aristotle was just as concerned as Plato was to challenge popular, conventional, contemporary cultural notions, especially concerning what was the right and best (one and the same, of course) way to live, even though he may have been disposed temperamentally to give them more consideration, especially if they were long-standing notions, than Plato was.