In publishing a Second Edition (1875) of the Dialogues of Plato in English, I had to acknowledge the assistance of several friends: of the Rev. G.G. Bradley, Master of University College, now Dean of Westminster, who sent me some valuable remarks on the Phaedo; of Dr. Greenhill, who had again revised a portion of the Timaeus; of Mr. R.L. Nettleship, Fellow and Tutor of Balliol College, to whom I was indebted for an excellent criticism of the Parmenides; and, above all, of the Rev. Professor Campbell of St. Andrews, and Mr. Paravicini, late Student of Christ Church and Tutor of Balliol College, with whom I had read over the greater part of the translation. I was also indebted to Mr. Evelyn Abbott, Fellow and Tutor of Balliol College, for a complete and accurate index. In this, the Third Edition, I am under very great obligations to Mr. Matthew Knight, who has not only favoured me with valuable suggestions throughout the work, but has largely extended the Index (from 61 to 175 pages) and translated the Eryxias and Second Alcibiades; and to Mr Frank Fletcher, of Balliol College, my Secretary. I am also considerably indebted to Mr. J.W. Mackail, late Fellow of Balliol College, who read over the Republic in the Second Edition and noted several inaccuracies. In both editions the Introductions to the Dialogues have been enlarged, and essays on subjects having an affinity to the Platonic Dialogues have been introduced into several of them. The analyses have been corrected, and innumerable alterations have been made in the Text. There have been added also, in the Third Edition, headings to the pages and a marginal analysis to the text of each dialogue. At the end of a long task, the translator may without impropriety point out the difficulties which he has had to encounter. These have been far greater than he would have anticipated; nor is he at all sanguine that he has succeeded in overcoming them. Experience has made him feel that a translation, like a picture, is dependent for its effect on very minute touches; and that it is a work of infinite pains, to be returned to in many moods and viewed in different lights.