To save time for anyone reading along, the heart of the sections in Philebus and Seneca I am referring to are:
SOCRATES: I omit ten thousand other things, such as beauty and health and strength, and the many beauties and high perfections of the soul: O my beautiful Philebus, the goddess, methinks, seeing the universal wantonness and wickedness of all things, and that there was in them no limit to pleasures and self-indulgence, devised the limit of law and order, whereby, as you say, Philebus, she torments, or as I maintain, delivers the soul. — What think you, Protarchus?
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SOCRATES: Have pleasure and pain a limit, or do they belong to the class which admits of more and less?
PHILEBUS: They belong to the class which admits of more, Socrates; for pleasure would not be perfectly good if she were not infinite in quantity and degree.
SOCRATES: Nor would pain, Philebus, be perfectly evil. And therefore the infinite cannot be that element which imparts to pleasure some degree of good. But now — admitting, if you like, that pleasure is of the nature of the infinite — in which of the aforesaid classes, O Protarchus and Philebus, can we without irreverence place wisdom and knowledge and mind? And let us be careful, for I think that the danger will be very serious if we err on this point.
PHILEBUS: You magnify, Socrates, the importance of your favourite god.
SOCRATES: And you, my friend, are also magnifying your favourite goddess; but still I must beg you to answer the question.
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SOCRATES: And whence comes that soul, my dear Protarchus, unless the body of the universe, which contains elements like those in our bodies but in every way fairer, had also a soul? Can there be another source?
PROTARCHUS: Clearly, Socrates, that is the only source.
SOCRATES: Why, yes, Protarchus; for surely we cannot imagine that of the four classes, the finite, the infinite, the composition of the two, and the cause, the fourth, which enters into all things, giving to our bodies souls, and the art of self-management, and of healing disease, and operating in other ways to heal and organize, having too all the attributes of wisdom; — we cannot, I say, imagine that whereas the self-same elements exist, both in the entire heaven and in great provinces of the heaven, only fairer and purer, this last should not also in that higher sphere have designed the noblest and fairest things?
PROTARCHUS: Such a supposition is quite unreasonable.
SOCRATES: Then if this be denied, should we not be wise in adopting the other view and maintaining that there is in the universe a mighty infinite and an adequate limit, of which we have often spoken, as well as a presiding cause of no mean power, which orders and arranges years and seasons and months, and may be justly called wisdom and mind?
PROTARCHUS: Most justly.
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We can find the same point made by Seneca in the following letters:
Quote Seneca’s Letters – Book I – Letter XVI: This also is a saying of Epicurus: “If you live according to nature, you will never be poor; if you live according to opinion, you will never be rich.” Nature’s wants are slight; the demands of opinion are boundless. Suppose that the property of many millionaires is heaped up in your possession. Assume that fortune carries you far beyond the limits of a private income, decks you with gold, clothes you in purple, and brings you to such a degree of luxury and wealth that you can bury the earth under your marble floors; that you may not only possess, but tread upon, riches. Add statues, paintings, and whatever any art has devised for the luxury; you will only learn from such things to crave still greater. Natural desires are limited; but those which spring from false opinion can have no stopping point. The false has no limits.
Quote Seneca’s Letters – To Lucilius – 66.45: “What can be added to that which is perfect? Nothing otherwise that was not perfect to which something has been added. Nor can anything be added to virtue, either, for if anything can be added thereto, it must have contained a defect. Honour, also, permits of no addition; for it is honourable because of the very qualities which I have mentioned.[5] What then? Do you think that propriety, justice, lawfulness, do not also belong to the same type, and that they are kept within fixed limits? The ability to increase is proof that a thing is still imperfect.”“