Do you realize why, if an Epicurean admitted that pleasure has no natural limit, the result would be the destruction of the view that be best life is one of pleasure?
Think about this: as Plato argued in his “Philebus” dialogue, a thing which has no limit is a thing which can be measured in different quantities, with some quantities more and some quantities less than another. If you want to live the “best” life, however, you must know which quantity is best so you can pursue that particular quantity.
In the case of Pleasure, if pleasure has no natural limit, how are you to know WHICH quantity of pleasure to measure for yourself? Should you not always be pushing yourself as hard as you can to experience more, more, more, without regard to pain or anything else?
So once you see that pleasure can always be measured in greater or smaller quantities, must you not look to some OTHER factor – outside of pleasure and different from pleasure – by which to decide how much pleasure to pursue for yourself?
And if there is some factor outside of pleasure, and separate from pleasure, which is required in order to determine how to live the best life, is not then that outside factor, which is not pleasure, the ruler of pleasure? And does this not show that pleasure alone is not the greatest good?
The answer is, “Yes, it would – *if* pleasure has no natural limit established by Nature herself.”
So Epicurus met this argument head-on. Epicurus knew that if pleasure is admitted to be ruled by some other factor which is not itself pleasurable, or which is valued only because it leads to pleasure, then pleasure itself cannot be the highest good.
And so Epicurus worked to identify the “limit” of pleasure. And he did so not, as some wish to argue, as an endorsement that it is always best to seek pleasure in modest quantities, or pleasures of a particular (e.g. “simple”) type. Those who reach this conclusion have unwittingly accepted Plato’s argument and destroyed the foundation of pleasure as the guide of life.
The argument that modest or moderate quantities, or pleasures of a particular type, are “always” best is an abstraction which does not address the particular situations of particular people. If in fact a particular person is able to achieve greater pleasure under his or her circumstances, then there is no reason for that person not to pursue that quantity or type of pleasure which is suited for his circumstances. And so Epicurus made the point explicitly: PD10 “If the things that produce the pleasures of profligates could dispel the fears of the mind about the phenomena of the sky and death and its pains, and also teach the limits of desires (and of pains), we should never have cause to blame them: for they would be filling themselves full with pleasures from every source and never have pain of body or mind, which is the evil of life.”
And so it is essential to see that the assertion that it is “always” better to seek modest pleasure is an assertion of a logical abstraction which would be – if true – superior to the guidance of pleasure itself. And so to warn us against this Epicurus said in his VS63: “Frugality too has a limit, and the man who disregards it is like him who errs through excess.”
Epicurus identified explained the natural limits of pleasure because in so doing he establishes the necessary foundation of Epicurean philosophy: Nature has given us pleasure alone as the guide of life, and we have no need to look for any ruling factor outside and separate from the nature of Pleasure itself.