Did Plato ever see a book by Anaxagoras?

Question

In Plato's Phaedo (98b), Socrates says he read books (plural in the Greek) by Anaxagoras, and at Apology (26d) he says these books can "sometimes be bought in the orchestra for many drachmas."  (The orchestra was the area for the chorus in a theater, "Sometimes" renders the Greek word "eniote.") There is no reason that books Socrates read could not have survived to Plato's time, but so far as I know there is no evidence books by Anaxagoras did survive either.  Aristotle gives fragments of Anaxagoras.

Is there evidence that whole books of Anaxagoras were still circulating in 4th century Athens?  Is there evidence that Plato would have seen them?  What are good sources on these questions?

Of course the plural on "books" here is compatible with the ancient authors who (according to Stanford Encyclopedia) say Anaxagoras only wrote one book, since "book" here could mean what were later called chapters of one book.

The question naturally expanded in the comments to whether Simplicius (ca. 480–560 CE) saw Anaxagoras' book.

I accepted an answer because I think it (together with Conifold's comment) does reflect the state of the evidence, though I think that answer draws far too strong a conclusion from the evidence.

It is normal in philosophy, and also in classics, to give and discuss evidence. 

So, for example, a comment by b_a notes that the standard reference Diels-Kranz cites specific passages of works as sources for each fragment of Anaxagoras.  Those sources are Plato, Aristotle, Theophrastus, Simplicius and others. Neither those ancient authors, nor Diels-Kranz have citations to Anaxagoras directly. So Simplicius will write of "The last book of Aristotle's Physics, which is the eight by number of the entire treatise." He cites the tenth book of Plato's Laws as "The tenth of the Laws." I call those citing Aristotle and Plato's works directly. But so far as I see his references to Anaxagoras are never like that but all of the form "Anaxagoras says." Now that does not prove he was not looking at the entirety of a book by Anaxagoras. But neither does it prove he was.

Diels and Kranz cite this evidence perhaps partly to overcome reasonable (or unreasonable) doubts, but more because it is interesting, and because it lets people look further into the questions.  That evidence fully justifies McKirahan saying Simplicus 600 years after Plato "had the text (or at least some of the text) of Anaxagoras before him" (cited in a comment by b_a).  McKirahan's parenthetic disclaimer explicitly leaves open the question of whether Simplicius had the full book of Anaxagoras or fragments of it.

The comment by Conifold gives very intriguing textual evidence with a link.  At that link you see they are not sure of the translation saying Epicurus "ordered" the best works of Anaxagoras--but it is likely the word was some form of "lambano" and would mean some kind of holding or having so this does not make much difference for my question. 

The frustrating point of this text for me is that the phrase "the best works" is represented on the papyrus by just "beltis" which is part of the Greek word for "best."  Both the article and the word ending are missing so that I do not see how you can even tell "best" here is a plural, let alone tell whether it means the best books, or best chapters, or best collected quotes of Anaxagoras.  If anyone does see how the Greek in this fragment settles that question I will be grateful.

In sum the evidence suggests Plato did see Anaxagoras's book and Simplicius may have.  But the strongest  textual evidence is in Plato, where it is not very explicit.  The rest of the textual evidence is quite thin and requires heavy interpretation.  

As to expert opinion, Barnes writing in the 1970s roundly excoriates anyone who would claim  "The so-called fragments are assuredly far from direct quotes from Anaxagoras’ book."  I have never seen anyone claim that though. I have never seen anyone even hint that Simplicius' fragments are not actual quotes. The question is whether Simplicius had Anaxagoras's book in front of him. And the only people I see assured of what happen are those who think Simplicius assuredly did have it.  

That notably includes Burnet  writing in 1924 as quoted by sand1 in a comment saying "Simplicius had access to a copy, doubtless in the library of the Academy".  Scholars today succeed at doubting all such specific claims about what was ever in the academy.  

Burnet had a lot of views on this topic that few people today share, most relevantly here:  "Burnet was known for defending novel interpretations of Plato and Socrates, particularly the view that the depiction of Socrates in all of Plato's dialogues is historically accurate...  Burnet believed that Socrates had been in his youth the disciple of Archelaus, a member of the Anaxagorean tradition."  

I remain persuaded that McKirahan published his parenthetical disclaimer that Simplicus saw "the text (or at least some of the text) of Anaxagoras" because he believed the state of the evidence demanded it. And I believe the evidence does demand it.

Answer 1

Leaving aside what is reasonable doubt and what is evidence enough, some remarks can be useful here.

Laertius, in a passage that is not exactly clear (II.10), seems to say that Anaxagoras was the first to have published a book. This has been understood as to have his books repeatedly copied and offered on the agora for anyone interested to buy, not for somebody particular. This corresponds well with the Passage 26d of the Apology. So until Plato's time access to Anaxagoras work seems to have been really unproblematic.

Aristotle discusses Anaxagoras numerous times and with details (e.g. Met.989a31) that make it most unlikely that he had not the book(s). Laertius also mentions (V.2) that Theophrastus (c. 370‑286 B.C.) wrote a book "A Reply to Anaxagoras" and also "On the Writings of Anaxagoras".

There seems no reasonable way to suggests that Anaxagoras work was not available to Plato. To prove that he read him in extenso, every word of it, is of course impossible but the case appears to be that it is the opposite claim that needs evidence. Tzamalikos Anaxagoras, Origen, and Neoplatonism : the Legacy of Anaxagoras to Classical and Late Antiquity (De Gruyter, 2016) contains insightful comments on what and how Anaxagoras was seen in later times.

For us Simplicius seems to be a main source of material and Burnet Early Greek Phphy (p. 257) writes that " Simplicius had access to a copy, doubtless in the library of the Academy".

McKirahan, Phphy before Socrates,( p.193) quotes some 16 fragments from Simplicius (6th,c.CE) and points them as "ample evidence that he had the text (or at least some of the text) of Anaxagoras before him" His parenthesis looks like and afterthought but it is probably a hint that he is aware of the view that Simplicius used Theophrastus and not the original. Barnes, Presocratics (p. 501) treats lightly the opinion that "The so-called fragments are assuredly far from direct quotes from Anaxagoras’ book" and adds "That view is deliciously wicked, but quite implausible; and the arguments on which it rests are worthless. It must be admitted, however, that the texts in Diels-Kranz are tidier than they should be: some of the fragments are patch-worked from various pages of Simplicius". However all this dispute concerns times nearly 1000 years after Plato.

Answer 2

Everything that Anaxagoras wrote survived until well after Plato's time. The so-called "fragments" of the Pre-Socratic philosophers are fragmentary only to us. They were transmitted to us by authors who had access to the originals, who lived up to hundreds of years after Plato. Nearly all the fragments of Anaxagoras were transmitted to us through the 6th century commentator Simplicius.

You can get an idea of the sources of the fragments from the footnotes to Arthur Fairbanks' translation of them, for example. But unfortunately he leaves out the introductions to the fragments that are interesting from the point of view of transmission, but looking at them in original (here available with Italian translation as well) demonstrates that Simplicius was quoting first-hand from the original books, which he cites by book number.

There is no question that the books were available to Plato. There is no direct evidence that he read them, but the passage in Phaedo is probably indirect evidence for it (if Plato respected Anaxagoras' views enough to mention them, he probably took the time to read them as well). Holger Thesleff (In Studies in Platonic Chronology, reprinted in Platonic Patterns p. 168) calls it "very likely" that he studied it, with the following note:

Cf. Ap[ology] 36d, Cra[tylus] 400a, 409ab, 413e, Ph[aedo] 72c, 97b ff. It is often thought that Socrates’ exposé of his philosophical development in Ph[aedo] 96a–102a actually concerns Plato himself. If this is so, Plato must have reached a considerable intellectual and philosophical maturity at an early age; but this is all very conjectural.