At this moment I think I would try to link this to the discussion with Philia as an example of trying to "measure pleasure by reason" and coming to a "reasoned understanding of pleasure" in order to dig out why the illustration seems (again, to me) so unsatisfying.
Part of the problem may be that this is an argument from Chrysippus, who has a Stoic was an arch-proponent of logic over
feeling, trying to make a ham-handed logic-based point about pleasure (which he detests as a feeling that distracts from virtue).
RE: An Epicurean Understanding of Pleasure
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Absolutely I agree with that, and I think most people at first glance see it that way too. That's "instinctively" the right approach, IMO. In fact I fluctuate on how much I really accept the opposite view myself. In my (admittedly small) mind, the only reason that the "subtractive" model "works" mentally is because you know that there are only two…
It's probably a significant part of the issue that pleasure (as a feeling) can never really be captured by a "logic" argument.
And of course in discussing THAT issue, this from "Torquatus" shouldn't be far from our minds as a huge red flag about the attempt to bridge logic and feeling, as Epicurus himself apparently warned against it:
[31] There are however some of our own school, who want to state these principles with greater refinement, and who say that it is not enough to leave the question of good or evil to the decision of sense, but that thought and reasoning also enable us to understand both that pleasure in itself is matter for desire and that pain is in itself matter for aversion. So they say that there lies in our minds a kind of natural and inbred conception leading us to feel that the one thing is t for us to seek, the other to reject. Others again, with whom I agree, finding that many arguments are alleged by philosophers to prove that pleasure is not to be reckoned among things good nor pain among things evil, judge that we ought not to be too condent about our case, and think that we should lead proof and argue carefully and carry on the debate about pleasure and pain by using the most elaborate reasonings.