Now, however, let us return to the investigated good [agathon ], and show what it is. For it appears that there is a different good in a different action [praxis ] and art [techne ]; since there is one good in the medical art, another in the art of commanding an army, and in a similar manner in the remaining arts. What therefore is the good in each ? Is it not that for the sake of which other things are effected by that art ? But this in the medical art indeed is health, in the art of commanding an army is victory, in the art of building a house, is a house, and something else in another art. And in every action and deliberate choice it is the end [telos ]; since all of them  perform other things for the sake of this. Hence, if there is one certain end of all actions this will be the practical good; but if there are many ends, these will be practical goods. The reasoning, however, in its transition arrives at the same thing [as was asserted by us in the beginning.]  But we must endeavour to render this still more clear. Because, therefore, it appears that there are many ends, and of these we choose some on account of others, such as wealth, flutes, and, in short, instruments; it is evident that all ends are not perfect. That however which is most excellent, appears to be something perfect; so that if there is only one certain perfect end, this will be what we investigate; but if there are many, it will be the most perfect of these. We denominate, however, that which is pursuable for its own sake, more perfect than that which is pursuable for the sake of something else; and that which is never eligible on account of another thing, than things which are eligible both on their own account, and for the sake of something else.  In short, the completely perfect is that which is always eligible on its own account, and never on account of something else. Felicity [eudaimonia ], however, especially appears to be a thing of this kind ; for we always choose this on its own account, and never on account of any thing else. But we choose honour [timé], and pleasure [hedone ], and intellect [noûs ], and every virtue [arete ], on their own account, indeed, (for though we should derive no farther advantage than what the possession of them affords, yet each of them would be the object of our choice) yet we also choose them for the sake of felicity. No one, however, chooses felicity for the sake of these, nor, in short, for the sake of any thing else. The same thing also appears to happen from that which enables a man to be sufficient to himself; for perfect good appears to be self-sufficient [autarkeia ]. But we call the self-sufficient that which is not only sufficient to him who lives a solitary life, but which is also sufficient to parents, and children, to a wife, and, in short, to friends and fellow-citizens; since man is naturally a political animal [politikon ó anthropos ]. A certain boundary, however, must be assumed of these things; for if good is to be extended to parents and their offspring, and to the friends of friends, there will be a procession to infinity. But this, indeed, we shall consider hereafter. We call, however, the self-sufficient that which subsisting by itself alone makes life eligible, and in want of nothing. But we think that felicity is a thing of this kind. And besides this, we think that it is the most eligible of all things, and is not connumerated [with any other good;] for if it were connumerated with even the smallest good, it is evident that it would be more eligible; since that which is added would become an excess of good. But a greater good is always more eligible. Felicity, therefore, appears to be something perfect and sufficient to itself, being the end of actions.
Perhaps, however, to say that felicity is the best of things, is to assert that which is acknowledged by all men; but it is requisite that we should yet more clearly say what it is. Perhaps, therefore, this will be effected, if the work [ergon ] of man is assumed. For as to the player on the flute, to the statuary, and to every artist, and in short to those who have a certain work and action, the good and the excellent appear to be in the work; this also may appear to be the case with man, if he has a certain work. Whether, therefore, are there certain works and actions indeed of a carpenter and a shoe-maker; but of man is there no work, and is he naturally indolent ? Or shall we say, that as of the eye, the hand and the foot, and in short of each of the parts of the body, there appears to be a certain work, so likewise of man, shall we admit that besides all these there is a certain work ? What then will this work be ? For to live [zoe] appears to be common also to plants [as well as to men]. But the peculiar work of man is now investigated. The nutritive and augmentative life, therefore, must be rejected. And a certain sensitive life will be consequent to this. It appears, however, that this also is common to a horse and an ox, and to every animal. A certain practic life, therefore, accompanied with reason remains. But of this, one kind is obedient to reason [logos ], but the other possesses reason, and energizes [energeia ] discursively. Since this life, however, is predicated in a twofold respect [i. e. according to energy and according to habit [ethos ],] it must be admitted to subsist according to energy [energeia]; for this appears to be predicated according to a more principal mode of subsistence. But if the work of man is the energy of soul according to reason, or not without reason; and we say that the same thing is the work of the human species and of a worthy man, just as the same thing is the work of a harper and of a good harper, and in short, this is the case in all things, excellence according to virtue being added to the work; for the work of a harper is to play on the harp, and of a good harper to play well on it;—if this be the case, and we admit the work of man to be a certain life, and this to be the energy of the soul [psyches energeian], and actions in conjunction with reason [praxeis meta logou], but by a worthy man, these things are well and beautifully performed, and every thing is well accomplished according to its proper virtue ;—if this be the case, human good will be the energy of soul according to virtue. But if there are many virtues, it will be the energy of soul according to the best and most perfect virtue ; and besides this, in a perfect life. For as one swallow does not make spring, nor one day; so neither does one day, nor a little time, make a man blessed and happy. Let this, therefore, be a description of the good; for it is necessary, perhaps, [as in a picture,] first to delineate, and afterwards add the colours. But it would seem, that any one may be able to educe, and distinctly arrange things which are well delineated, and that time is the inventor of, or a good co-operator with, things of this kind; whence, also, accessions are made to the arts; for any one may add to what is wanting. It is also requisite to call to mind what has been before said, and not to search for accuracy similarly in all things, but investigate it in each according to the subject matter, and so far as is appropriate to the method [pertaining to the inquiry]. For a carpenter and a geometrician investigate a right angle differently; the former, indeed, so far as is useful to his work; but the latter explores what it is, or what the quality is which it possesses; for he is a contemplator of truth . After the same manner, therefore, we must proceed in other things, lest what is superfluous should become more abundant than the works themselves. Neither must the cause be required similarly in all things, but in some, as, for instance, concerning principles [arche ], it is sufficient to have shown properly that they are. But the subsistence of a thing (to on) is the first thing and the principle. Of principles, however, some are surveyed by induction, others by sense , others from a certain custom, and others in a different way. But we should endeavour to discuss every thing, so far as its nature permits, and should earnestly apply ourselves to define well; for this is of great importance with respect to what is consequent. The principle, therefore, appears to be more than half of the whole, and many of the things which are objects of inquiry become manifest through it.