Xenephon's Memorabiliva of Socrates is available online in English here:http://thriceholy.net/Texts/Memorabilia.html
The section on the choice of Heracles is in Book II, Chapter I, from paragraphs 21-34:O wretched mortal, desire not what is soft, lest you find what is hard.
21. Prodicus the sophist, also, in his narrative concerning Hercules, which indeed he declaims to most people as a specimen of his ability, expresses a similar notion respecting virtue, speaking, as far as I remember, to the following effect: For he says that Hercules, when he was advancing from boyhood to manhood, a period at which the young, becoming their own masters, begin to give intimations whether they will enter on life by the path of virtue or that of vice, went forth into a solitary place, and sat down, perplexed as to which of these two paths he should pursue; 22. and that two female figures, of lofty stature, seemed to advance towards him, the one of an engaging and graceful mien, gifted by nature with elegance of form, modesty of look, and sobriety of demeanor, and clad in a white robe; the other fed to plumpness and softness, but made up both in her complexion, so as to seem fairer and rosier than she really was, and in her gesture, so as to seem more upright than she naturally was; she had her eyes wide open, and a robe through which her beauty would readily show itself; she frequently contemplated her figure, and looked about to see if any one else was observing her; and she frequently glanced back at her own shadow. 23. As they approached nearer to Hercules, she, whom I first described, came forward at the same pace, but the other, eager to get before her, ran up to Hercules, and exclaimed, “I see that you are hesitating, Hercules, by what path you shall enter upon life; if, then, you make a friend of me, I will conduct you by the most delightful and easy road, and you shall taste of every species of pleasure, and pass through life without experiencing difficulties. 24. In the first place, you shall take no thought of wars or state affairs, but shall pass your time considering what meat or drink you may find to gratify your appetite, what you may delight yourself by seeing or hearing, what you may be pleased with smelling or touching, with what objects of affection you may have most pleasure in associating, how you may sleep most softly, and how you may secure all these enjoyments with the least degree of trouble. 25. If an apprehension of want of means, by which such delights may be obtained, should ever arise in you, there is no fear that I shall urge you to procure them by toil or suffering either of body or mind; but you shall enjoy what others acquire by labor, abstaining from nothing by which it may be possible to profit, for I give my followers liberty to benefit themselves from any source whatever.”
26. Hercules, on hearing this address, said, “And what, O woman, is your name?” “My friends,” she replied, “call me Happiness, but those who hate me, give me, to my disparagement, the name of Vice.”
27. In the meantime the other female approached, and said, “I also am come to address you, Hercules, because I know your parents, and have observed your disposition in the training of your childhood, from which I entertain hopes that if you direct your steps along the path that leads to my dwelling, you will become an excellent performer of whatever is honorable and noble, and that I shall appear more honorable and distinguished in goodness. I will not deceive you, however, with promises of pleasure, but will set before you things as they really are, and as the gods have appointed them; 28. for of what is valuable and excellent, the gods grant nothing to mankind without labor and care; and if you wish the gods, therefore, to be propitious to you, you must worship the gods; if you seek to be beloved by your friends, you must serve your friends; if you desire to be honored by any city, you must benefit that city; if you claim to be admired by all Greece for your merit, you must endeavor to be of advantage to all Greece; if you are anxious that the earth should yield you abundance of fruit, you must cultivate the earth; if you think that you should enrich yourself from herds of cattle, you must bestow care upon herds of cattle; if you are eager to increase your means of war, and to secure freedom to your friends and subdue your enemies, you must learn the arts of war, and learn them from such as understand them, and practice how to use them in the right way; or if you wish to be vigorous in body, you must accustom your body to obey your mind, and exercise it with toil and exertion.”
29. Here Vice, interrupting her speech, said (as Prodicus relates), “Do you see, Hercules, how difficult and tedious a road to gratification this woman describes to you, while I shall lead you, by an easy and short path, to perfect happiness?”
30. “Wretched being,” rejoined Virtue, “of what good are you in possession? Or what real pleasure do you experience, when you are unwilling to do anything for the attainment of it? You, who do not even wait for the natural desire of gratification, but fill yourself with all manner of dainties before you have an appetite for them, eating before you are hungry, drinking before you are thirsty, procuring cooks that you may eat with pleasure, buying costly wines that you may drink with pleasure, and running about seeking for snow in summer; while, in order to sleep with pleasure, you prepare not only soft beds, but couches, with rockers under your couches, for you do not desire sleep in consequence of labor, but in consequence of having nothing to do; you force the sensual inclinations before they require gratification, using every species of contrivance for the purpose, and abusing male and female; for thus it is that you treat your friends, insulting their modesty at night, and making them sleep away the most useful part of their day. 31. Though you are one of the immortals, you are cast out from the society of the gods, and despised by the good among mankind; the sweetest of all sounds, the praises of yourself, you have never heard, nor have you ever seen the most pleasing of all sights, for you have never beheld one meritorious work of your own hand. Who would believe you when you give your word for anything? Or who would assist you when in need of anything? Or who, that has proper feeling, would venture to join your company of revellers? for while they are young they grow impotent in body, and when they are older they are impotent in mind; they live without labor, and in fatness, through their youth, and pass laboriously, and in wretchedness, through old age; ashamed of what they have done, oppressed with what they have to do, having run through their pleasures in early years, and laid up afflictions for the close of life. 32. But I am the companion of the gods; I associate with virtuous men; no honorable deed, divine or human, is done without me; I am honored, most of all, by the deities, and by those among men to whom it belongs to honor me, being a welcome co-operator with artisans, a faithful household guardian to masters, a benevolent assistant to servants, a benign promoter of the labors of peace, a constant auxiliary to the efforts of war, an excellent sharer in friendship. 33. My friends have a sweet and untroubled enjoyment of meat and drink, for they refrain from them till they feel an appetite. They have also sweeter sleep than the idle; and are neither annoyed if they lose a portion of it, nor neglect to do their duties for the sake of it. The young are pleased with praises from the old; the old are delighted with honors from the young. They remember their former acts with pleasure, and rejoice to perform their present occupations with success; being, through my influence, dear to the gods, beloved by their friends, and honored by their country. And when the destined end of life comes, they do not lie in oblivion and dishonor, but, celebrated with songs of praise, flourish for ever in the memory of mankind. By such a course of conduct, O Hercules, son of noble parents, you may secure the most exalted happiness.”
34. Nearly thus it was that Prodicus related the instruction of Hercules by Virtue; adorning the sentiments, however, with far more magnificent language than that in which I now give them. It becomes you, therefore, Aristippus, reflecting on these admonitions, to endeavor to think of what concerns the future period of your life.
On the Pythagorean Y, see for example here:http://vunex.blogspot.com/2006/11/garde ... paths.html