Here’s the first, Vatican Saying 27:
Ἐπὶ μὲν τῶν ἄλλων ἐπιτηδευμάτων μόλις τελειωθεῖσιν ὁ καρπὸς ἔρχεται, ἐπὶ δὲ φιλοσοφίας συντρέχει τῇ γνώσει τὸ τερπνόν· οὐ γὰρ μετὰ μάθησιν ἀπόλαυσις, ἀλλὰ ἅμα μάθησις καὶ ἀπόλαυσις.Bailey translates:
‘In all other occupations the fruit comes painfully after completion, but in philosophy pleasure goes hand in hand with knowledge; for enjoyment does not come after comprehension, but comprehension and enjoyment are simultaneous.’Compare Diogenes of Oinoanda fr. 33.VI.11–VII.10 Smith for the idea that the pleasure and the cause of the pleasure can be simultaneous: we do not eat and then afterwards experience pleasure because of eating nor do we ejaculate and then later experience pleasure because of that . In these cases what causes the pleasure and the pleasure itself are simultaneous.
This Saying is mostly concerned with pointing out that knowledge and pleasure come about simultaneously (at the moment I come to know something I simultaneously enjoy knowing that something). Knowing is just all by itself something pleasant. I don’t need to wait for that knowledge to be useful or to lead to some later pleasure; it’s pleasant all by itself and the pleasure occurs as soon as something is known. So, like the Diogenes of Oinoanda fragment, it might well be aimed at dispelling the idea that the Epicureans think that knowledge—like virtue—is good only in a crude way because of some later pleasure that it might produce. Instead, they want to say that knowledge is good because it is pleasant immediately and all by itself. The chronological claim is perhaps best understood as a claim about the nature of the value of knowledge. Knowledge is intrinsically pleasant and therefore valuable; knowledge does not have to wait to cause some later pleasure for it to be valuable.
The Epicureans clearly feel some pressure to recognise a value of knowledge that is not merely contingent on its producing some later pleasure while still holding firm to their hedonist axiology. Perhaps the idea is this: It is not pleasant to know some trigonometry just because it will allow me later on to build a house efficiently and live in a secure and water-tight dwelling. Yes, it will do that. But knowing that the square on the hypotenuse is equal to etc. etc. is just pleasant all by itself. Or, if we want a more specific example of some Epicurean ‘philosophy’, perhaps it is not pleasant to know that lightning is not caused by divine anger just because that will allow me to live a life free from superstitious anxieties. Yes, it will do that. But knowing that lightning is caused thus-and-so is just pleasant all by itself. (Compare Ep. Hdt. 78–9 and Ep. Pyth. 86 which also stress the necessity of a sufficient knowledge of such things for living a good life.)
It is still the case that the value of knowledge lies in its being pleasant, of course, but its pleasantness is intrinsic and inseperable. The Saying does not say whether it continues to be pleasant to know something. A lot would depend on the precise meaning of gnōsis and mathēsis. For example: if the latter means ‘learning’ in the sense of the event of coming to know something, then it will not follow that just because this is all by itself pleasant just when it happens, it will continue to be pleasant to have learned something. But the sense of the event of coming to know something makes best sense of the claim there need be no time-lag between the mathēsis and the pleasure. (This is not a common word in Epicurus. Nor is the cognate verb common. But compare SV 74: ‘In philosophical shared inquiry the one who is beaten gains more according to how much more he learns [prosemathen].’) The former, however, gnōsis, is more likely to mean an on-going state of knowing or understanding. (See, for example, its use in Ep. Hdt. 78–9). (It’s a familiar problem with ancient philosophical claims for the pleasantness of knowing that it is sometimes unclear whether they mean that it is pleasant to come-to-know or to continue-to-know, or both. And the reasons for making either claim or both claims might have to be different.)
 I’ve been thinking a bit about Epicureanism again lately because Pamela Gordon very kindly sent me a copy of her new book, The Invention and Gendering of Epicurus (Ann Arbor, 2012): very interesting it is too.
 For a recent discussion see D. N. Sedley, ‘Diogenes of Oenoanda on Cyrenaic hedonism’, PCPS 48 (2002), 159–74