As far as the "feelings are two," I fall back on the modern psychological research on valence and activation. You'll see some of this on this forum if you search for circumplex or Dr. Lisa Feldman Barrett, https://lisafeldmanbarrett.com/
And while I am glad to have any argument in support of Epicurus, modern research manifestly cannot have been on Epicurus' mind when he formulated his philosophy.
Why is this? If the absence of pain is pleasurable, then shouldn't the absence of pleasure be painful, by necessity? When pleasure simply fades away, what are we left with if not pain?
Given Epicurus' framework, I think it is clear that Epicurus would say that 'absence of pleasure' equals pain.
