pursuing the details on difficult topics can be very motivational.
We also know that for example Epicurus divided things into "natural and necessary," and that that distinction was significant to be recorded several places very clearly, including the principal doctrines, the letter to Menoeceus, and the vatican sayings
To that, I'd say "Bingo!" According to On Choices and other quoted material, Epicurus used the words katastematic and kinetic. Yes, I will continue to "assert" that. But *maybe* they weren't central to his philosophy because THEY'RE BOTH PLEASURES. He didn't see the need to belabor the point.
This discussion has me thinking further about pleasures v desires. Whether with nefarious intent or through misunderstanding, it seems to me that the Platonic/Ciceronian treatment conflates and confuses pleasure with desire, and that this is a major cause or the katastematic-kinetic brouhaha.
Don's quote seems to hit on a key: of course there are different types of pleasure, but they're all pleasure. And pleasure is the goal, not any particular type of pleasure. More specifically, the experience of the feeling which is pleasure is the goal (or guide, if you prefer).
As to Cassius' quote, Epicurus clearly has a division of "things into natural and necessary". Correct me if I'm missing something, but I've never found a connection between pleasure and natural and necessary in any of the writings of Epicurus. The connection that he consistently makes, in all cases (at least in translation) is between natural and necessary and desires. In the PDs it's between desires and pains. But never pleasures.
Why? My thinking is that pleasure is typically a result. Desires are something that we can tangibly work with. Epicurus' concern is with describing practice, with things anybody can do to achieve pleasure. He doesn't care what type of pleasure you achieve, he's concerned with how you go about achieving pleasure. And to him, you do this by working with your desires and with your pains. If you understand your desires, you will be more effective at achieving pleasure. As you minimize your various pains, these will by definition be replaced with pleasure. But you must always remember that your guide and goal is pleasure. Understanding desires and removing pains are only tools for pursuing pleasure. We can also pursue various pleasures for pure enjoyment, but for an effective practice to achieve lasting pleasure he focused on working with desires and on things which cause pain.
To me, this is the important concern for a practicing Epicurean. And the Golden Ones and The Cow have done a fine job of diverting the focus to sorting out fancy pleasures. But since they have been so successful, it's useful for us to untangle the mess that they've created.