The remainder of Plato's life, after his final return from Sicily, was devoted to his school. It was passed in great ease and honor, notwithstanding the troubles, domestic and foreign, in which Athens was involved, and the succession of wars which harassed, impover- ished, and depopulated Greece. He died B.C. 347, in the year in which Olynthus was taken by Philip of Macedon, and, according to Seneca, on the same day of the same month in which he had been born ("Platoni diligentine sua? beneficio contigisse, quod natali suo decessit, et annum unum atque octogesimum implevit, sine ulla deductione," Epist. vi, G [58], § 31). He adds that hence the Magi, then at Athens, sacrificed to him, as being of a nature more than human ("amplioris fu- isse sortis quam humana? rati") — thus furnishing anoth- er evidence of his mythical divinity.
From this account of the life of Plato it will be seen that he had large and unsatisfactory acquaintance with the social ailments and political conditions of his time ; that he held intimate intercourse with the most distin- guished personages of the period ; that he was brought into close connection with Socrates and the Socratic family, with the Heraclitean, Megaric, Pythagorean, and other schools; that his education was large and libera) ; his studies, observation, and travels varied and extensive; his talents versatile and lofty; that he unit- ed the genius of the poet, the aptitudes of the rhetori- cian, the skill of the dialectician, the reason of the phi- losopher, with the diligence of a scholar, the training of a man of the world, and the propensities of a states- man. He was thus full-armed, and prepared to convert to his own use all former knowledge and speculation. How he employed his gifts and the materials at his command will be manifested by the consideration of his literary and philosophical career.
II. Writings. — The literary remains which pass under the name of Plato are among the most extensive monu- ments of the classic age of Athens, notwithstanding the disfavor with which he regarded writing as a mode of instruction, and his repeatedly expressed preference for oral communication in the treatment of philosophical problems (Phcedo, p. 276 ; Grote, Plato, vol. i, ch. vi, p. 221-232). It would be pressing too far the remarkable declaration contained in the Seventh p]pistle : " I have never myself written anything upon these subjects; there neither is, nor shall there ever be, a treatise of Plato" — it would be pressing this declaration too far to conclude from it that Plato had written nothing up to that late period of his life. It would be pressing it still further, and more unwarrantably, to receive it as evidence that he never wrote anything at all. The genuineness of the epistle is not above suspicion, and lias often been denied. Moreover, Plato adds: "The opinions called by the name of Plato are those of Socra- tes, in his days of youthful vigor and glory." These opinions might have been published by writing, as well as by oral delivery, and still have been disclaimed; and there is a bold fiction, or Platonic myth, in ascribing them to Socrates at any period of his life ; but it ena- bled Plato to disconnect himself from all personal re- sponsibility for the doctrines set forth by him. It is certain that Plato discountenanced the written promul- gation of philosophy, and that his writings were not designed for general circulation, or for the acquisition of literarv or other fame, but as summaries fur his school,
and for the attestation of his views. This is confirmed by the story of Hermodorus selling the Platonic treatises in Sicily, and by the proverb founded thereon: \6yoiaiv 'Ep/toowpoc kfiTTopevtrcti. Yet, in despite of this aver- sion, which rested on grounds of personal ease and secu- rity, as well as on the exclusiveness of sect ami other philosophic reasons, the Optra Platonis constitute a very copious collection. They consist of thirty-six works, iir fifty-six books, counting the thirteen epistles as one book. To these are appended, in many editions of Plato, seven treatises generally recognised to be spuri- ous. Of the thirty -six works habitually ascribed to Plato, only two have wholly escaped challenge on the score of authenticity.
It is very important for the student of philosophy that the genuine treatises of Plato should be clearly separated from those that are doubtful or illegitimate. It is equally important that none should be repudiated from fanciful conjecture. The task of criticism seemed to have been adequately executed by the great scholars of the Museum at Alexandria, and the results which they reached were not seriously questioned till the close of the last century. Since that period a succession of acute and too ingenious philologians in Germany, com- mencing with Tennemann and Schleiermacher, have undertaken to determine the legitimacy, the order, and the approximate dates of the several Platonic treatises, in accordance with their own notion of his latent mean- ing; and have rejected such of the Dialogues as failed to harmonize in form, finish, or sentiment with their preconceived views .of the Platonic scheme.' These criticisms, arrangements, and rejections do not accord with each other: there are continual dissonances among these organizers and repudiators. If they are followed, everything becomes a quaking bog beneath the feet of the inquirer. It is safer and more satisfactory to acqui- esce in the conclusions of the ancients, who had means of judging at their command denied to us, and to receive as Plato's what, has been received as Plato's under their authority. To this conclusion Mr. Grote comes after a diligent and minute examination of the Platonic canon, and of all that has been alleged on the part of the op- ponents. He shows that the accepted canon rests upon the scheme of Thrasylhis, formed about the reign of Tiberius ; that the canon of Thrasylhis rests upon the classification of Aristophanes of Byzantium, and the ar- rangements of the Alexandrian Library; that the Alex- andrian critics probably derived their knowledge, medi- ately or immediately, from Xcnocrates and the early- Academy itself; and that the Platonic documents were attested by their careful preservation, transcription, and collation in the Academy itself— the house and manu- scripts of Plato having been bequeathed by him to the school. The chain of evidence is as complete as pos- sible for the determination of the authorship of ancient works. The direct positive evidence is valuable and irrefragable, but limited. It is almost entirely confined to references in Aristotle to treatises with which he connects the name of Plato; references to passages in Plato, but without mention of his name; and references which can scarcely be explained otherwise than as ref- erences to evident passages in Plato. The Dialogues thus accredited are, first, the Republic, Timaeus, and Laws; second, the Phaedon, Banquet. Phsedrus, and Gorgias; third, the Meno, Hippias Minor, and Menex- enus; fourth, the Theaetetus, Philebus, and Sophistes; and lastly, the Politicus, Apology, Lysis, Laches, and perhaps the Protagoras, Kuthydemus, and Cratylus.