The Epistles (Greek: Ἐπιστολαί; Latin: Epistolae) of Plato are a series of thirteen letters traditionally included in the Platonic corpus. Their authenticity has been the subject of some dispute, and scholarly consensus has shifted back and forth over time. They were "generally accepted as genuine until modern times"; but by the close of the nineteenth century, many philologists (such as Richard Bentley, Christoph Meiners, and Friedrich Ast) believed that none of the letters were actually written by Plato. Now every letter except the First has some defenders of its authenticity. The Twelfth is also widely regarded as a forgery, and the Fifth and Ninth have fewer supporters than the others.
The Epistles focus mostly on Plato's time in Syracuse and his influence on the political figures Dion and Dionysius. They are generally biographical rather than philosophical, although several, notably the Seventh Letter, gesture at the doctrines of Plato's philosophy. Only two, the Second and Seventh, directly reference Plato's teacher Socrates, the major figure within his philosophical dialogues.
The two letters that are most commonly claimed to have actually been written by Plato are the Seventh and the Eighth, on the supposition that these were open letters and therefore less likely to be the result of invention or forgery. This is not so much because of a presumption in favor of an open letter's authenticity as because of a presumption against that of a private letter: the preservation of the former is unsurprising, while the preservation, dissemination, and eventual publication of the latter requires some sort of explanation. Nevertheless, even the Seventh Letter has recently been argued to be spurious by prominent scholars, such as Malcolm Schofield, Myles Burnyeat, and Julia Annas. George Boas argues that all of the Epistles, including the Seventh, are spurious, a conclusion accepted also, and more recently, by Terence Irwin. On the other hand, George Grote, Anton Ræder, Novotny, Harward, and Bluck reject only the First; and Bentley accepted all of them.
The other letters enjoy varying levels of acceptance among scholars. The Sixth, Third, and Eleventh have the greatest support of the remaining letters, followed by the Fourth, Tenth, Thirteenth, and Second Letter; fewer scholars consider the Fifth, Ninth, and Twelfth to be genuine, while almost none dispute that the First is spurious.
If the Epistles are genuine—and some of the greatest scholars and historians hold they are—we know more of the life of Plato than of any other ancient philosopher.' Even apart from the Epistles we know a good deal. Besides what we may infer from the dialogues, we have one or two statements resting on the authority of Hermodoros, who was a member of the Academy in Plato’s time, and these give us certain fixed points to start from. The later Lives are almost entirely mythical. It is conceivable that they may contain one or two stray facts derived from older sources now lost, but their general character is such that it is safer to neglect them in the first instance. The Epistles on the other hand, are free from this mythology, which is the more remarkable as Plato’s own nephew, Speusippos, already credited him with a miraculous birth. If, then, the Epistles are forgeries, they are at least the work of a sober and well-informed writer, whose use of the Attic dialect proves him to have been Plato’s contemporary. It would have been impossible to find anyone fifty years later who could handle the language as he does. Even the oldest and most successful of the spurious dialogues betray themselves at every turn. We may, indeed, go so far as to say that the supposed forger of the Epistles must have been a man of almost unparalleled literary skill, or he could not have reproduced so many of the little peculiarities that marked Plato’s style at the very time of his life to which the Epistles profess to belong, though with just those shades of difference we should expect to find in letters as contrasted with more elaborate literary work. I believe that all the letters of any importance are Plato’s, and I shall therefore make use of them. As, however, there are still eminent scholars who are not convinced, I shall warn the reader when I have occasion to do so.
The genuineness of the Epistles has been maintained by scholars like Bentley and Cobet, and by historians like Grote and E. Meyer In practice most accounts of Plato really depend on them, though that is disguised by the custom of referring instead to Plutarch’s Life of Dion. Plutarch, however, is obviously dependent on the Epistles for most, if not all, of what he tells us; so this is an illegitimate evasion. I should add that the First Epistle stands by itself In my judgement, it has got into its present place by mistake. It is a genuine fourth-century letter, but I do not think the writer, whoever he was, meant to pass for Plato at all. I do not think either that he was Dion or meant to pass for Dion.
The numbering of each letter is due solely to their placement in traditional manuscripts, and does not appear to follow any discernible principle. L. A. Post, in his edition of the Thirteen Epistles of Plato, presented them in the order in which he thought they were written: Thirteenth, Second, Eleventh, Tenth, Fourth, Third, Seventh, Eighth, and Sixth (the four letters universally recognized as spurious are placed following these nine).
The addressees of the Epistles fall into three main categories. Four are addressed to Dionysius II of Syracuse (i, ii, iii, xiii), four to Dionysius' uncle Dion and his associates (iv, vii, viii, x), and five to various others (the Fifth to Perdiccas III of Macedon; the Sixth to Hermias of Atarneus, Erastus, and Coriscus; the Tenth to Aristodorus; the Eleventh to Laodamas; and the Ninth and Twelfth to Archytas).
The First Letter is addressed to Dionysius II of Syracuse, and is almost certainly a forgery. In it, Plato supposedly complains of his rude dismissal by Dionysius and predicts an evil end for him. It is interesting mainly for the number of quotations from the tragic poets which it preserves.
The Second Letter is addressed to Dionysius II of Syracuse in response to a supposed complaint he lodged against Plato and his associates that they were slandering him. The letter disclaims any responsibility for these slanders and further denies that they are even occurring. It then counsels Dionysius that a concern for his reputation after his death should incline him to repair his relationship with Plato, since the interactions of political men with the wise is a topic of constant discussion. From this subject, the letter turns to a deliberately enigmatic discussion of "the First," in which Plato warns Dionysius to never write these doctrines down and to burn this letter upon committing its contents to memory. The Second Letter is the source of the oft-cited remark that "no writing of Plato exists or ever will exist, but those now said to be his are those of a Socrates become beautiful and new (καλός καί νέος)."
R. G. Bury argues that the Second Letter is almost certainly inauthentic, based primarily upon conflicts between it and Plato's Seventh Letter and Bury's own conclusion is that its tone and content are decidedly un-Platonic. He considers it to be by the same author as the Sixth Letter.
The Third Letter is addressed to Dionysius II of Syracuse, complaining of two slanders aimed at Plato, viz. that he had prevented Dionysius II from transforming his tyranny into a monarchy and that Plato was to blame for all the maladministration in Syracuse. The letter responds by recounting Plato's activities in Syracuse, and has the flavor of an open letter.
Bury suggests that the Third Letter, if authentic, was probably written after Plato's third visit to Syracuse in 360 BC, and probably after Dion's seizure of power in 357 BC. He finds the tone to be anachronistic, however, remarks that the parallels to both the Apology of Socrates and the Seventh Letter argue against its authenticity.
The Fourth Letter is addressed to Dion, the uncle and (by this time) ouster of Dionysius II of Syracuse. It encourages Dion in his political efforts, but admonishes him not to forget about the importance of virtue. Bury finds the mixture of flattery and reproof in the letter to be at odds with Plato's friendlier relationship with Dion, even granting that it may be an open letter, and notes conflicts with the Seventh Letter that militate against its authenticity.
The Fifth Letter is addressed to Perdiccas III of Macedon, and counsels him to listen to the advice of one Euphraeus. It then proceeds to defend Plato's abstinence from politics. Most scholars doubt its authenticity.
The Sixth Letter is addressed to Hermias, tyrant of Atarneus, and to Erastus and Coriscus, two pupils of Plato residing in Scepsis (a town near Atarneus), advising them to become friends. The letter claims that Plato never met Hermias, contrary to the account given of the latter's life by Strabo; contains a number of parallels to the Second Letter concerning the value of combining wisdom with power, the utility of referring disputes to its author, and the importance of reading and re-reading it; and concludes that all three addresses should publicly swear an oath to strange deities, and to do so half-jestingly. For these reasons, Bury concludes that Sixth Letter is inauthentic and shares its author with the Second Letter.
The Seventh Letter is addressed to the associates and companions of Dion, most likely after his assassination in 353 BC. It is the longest of the Epistles and considered to be the most important. It is most likely an open letter, and contains a defense of Plato's political activities in Syracuse as well as a long digression concerning the nature of philosophy, the theory of the forms, and the problems inherent to teaching. It also espouses the so-called "unwritten doctrine" of Plato which urges that nothing of importance should be committed to writing.
The Eighth Letter is addressed to the associates and companions of Dion, and was probably written some months after the Seventh Letter but before Dion's assassin, Callippus, had been driven out by Hipparinus. It counsels compromise between the parties of Dion and Dionysius the Younger, the former favoring democracy, the latter, tyranny. The compromise would be a monarchy limited by laws.
The Ninth Letter is addressed to Archytas. Bury describes it as "a colourless and commonplace effusion which we would not willingly ascribe to Plato, and which no correspondent of his would be likely to preserve." Despite the fact that Cicero attests to its having been written by Plato, most scholars consider it a literary forgery.
The Tenth Letter is addressed to an otherwise unknown Aristodorus, who is praised for having remained loyal to Dion, presumably during the latter's exile. The treatment of philosophy in simply moral terms, without any reference to intellectual qualities, is foreign enough to Plato's treatment for Bury to declare the letter a forgery. In any event, it consists of a bare three sentences, covering nine lines in the Stephanus pagination.
The Eleventh Letter is addressed to one Laodamas, who apparently requested assistance in drawing up laws for a new colony. It refers to someone named Socrates, though the reference in the letter to the advanced age of Plato means that it cannot be the Socrates who is famous from the dialogues. Bury would allow the authenticity of the letter, were it not for the fact that it claims that this Socrates cannot travel on account of having been enervated by a case of strangury.
The Twelfth Letter is addressed to Archytas. It is only slightly longer than the Tenth Letter (four sentences, covering 12 lines in the Stephanus pagination), and considered to be spurious. It thanks Archytas for sending Plato some treatises, which it then goes on to praise effusively. Diogenes Laërtius preserves this letter in his Lives and Opinions of Eminent Philosophers, as well as the letter from Archytas which presumably occasioned the Twelfth Letter; this letter points to the treatises having been those of Ocellos of Lucania, a Pythagorean. Because the writings which are attributed to Ocellos are forgeries from the First Century BC, the Twelfth Letter is probably also a forgery, and by the same forger, intended to stamp the treatises with Plato's authority.
The Thirteenth Letter is addressed to Dionysius II of Syracuse, and appears to be private in character. The portrait of Plato offered here is in sharp contrast to that the disinterested and somewhat aloof philosopher of the Seventh Letter, leading Bury to doubt its authenticity.