I am likely to eventually break this out into a discussion of its own, but in this episode of the podcast Joshua brings up the question of "doxa" vs "episteme." From wikipedia:
Doxa (Ancient Greek: δόξα; from verb δοκεῖν, dokein, 'to appear, to seem, to think, to accept')[1] is a common belief or popular opinion. In classical rhetoric, doxa is contrasted with episteme ('knowledge').
We're having many simultaneous discussions about these issues right now, and it seems to me to be a good idea to try to be as clear as possible on what Epicurus considered to be "knowledge" vs what he considered to be "opinion."
"Knowledge" is a term to me that seems pretty clear, but probably "opinion" needs clarification as to whether "opinion" (as a word standing alone) is always to be viewed with suspicion, (probably yes?) while "knowledge" (as a word standing alone) implies something much more firm.
So that's something that needs to be clarified, but after that, the big issue is deciding what Epicurus held to be "known" and therefore relied upon with confidence vs "opinion" in which probability might be the best that can be said for it.
Specifically, as examples, did Epicurus hold PD01 and PD02 as written to be "knowledge" or some lesser standard, better described as "opinion."
Clearly Epicurus held many things mentioned in the letter to Pythocles to be open to numbers of possibilities, so as to those mostly astronomical issues I'd say those are "opinion."
But what about the affirmative statements in PD01, PD02? We'll also want to consider the many affirmative statements made in the letter to Menoeceus, and the most general of statements in Herodotus, but we ought not bite off more than can be chewed too quickly.
Were the positions stated in PD01 and PD02 considered by Epicurus to be "known" (knowledge)? Would he have admitted any aspect of them to be only "probably" true?
EDIT: It will presumably be important to incorporate as primary sources:
- What Lucretius says about this topic in Book 4 (a very long section but especially here
- What Diogenes of Oinoanda has to say about this in Fragment 5.
Fr. 5 [Others do not] explicitly [stigmatise] natural science as unnecessary, being ashamed to acknowledge [this], but use another means of discarding it. For, when they assert that things are inapprehensible, what else are they saying than that there is no need for us to pursue natural science? After all, who will choose to seek what he can never find? Now Aristotle and those who hold the same Peripatetic views as Aristotle say that nothing is scientifically knowable, because things are continually in flux and, on account of the rapidity of the flux, evade our apprehension. We on the other hand acknowledge their flux, but not its being so rapid that the nature of each thing [is] at no time apprehensible by sense-perception. And indeed [in no way would the upholders of] the view under discussion have been able to say (and this is just what they do [maintain] that [at one time] this is [white] and this black, while [at another time] neither this is [white nor] that black, [if] they had not had [previous] knowledge of the nature of both white and black.