the great disciple of Socrates. They are compositions which, whether we look to their style or their substance, far surpassed in beauty and in depth everything which had preceded them in philosophy, and they have been followed by very few works which will bear any comparison with their excellence. In the Platonic writings the form of dialogue was used probably for the first time as the vehicle of philosophical thought, and it started at once into perfection. In grace and ease, in poetical beauty and dramatic spirit, these Dialogues have never been equalled. In modern times they have frequently been imitated; and in our own country, the two philosophers who have imitated them most successfully, although they fall far short of their great original, are Berkeley and Shaftesbury.
7. The dialectic is the first part of the Platonic philosophy which must engage our attention. Dialectic, as I have said, is the science of ideas. We shall therefore have to inquire and ascertain as clearly as we can what ideas are in the Platonic sense of the term. This is an inquiry in which, from first to last, much labour has been expended. I am of opinion that, although the exertions of those who have explored this field are far from having been fruitless, much research and reflection are still required in order to set forth the nature of ideas in a perfectly distinct light, and in order to appreciate, at its true value, the Platonic theory which deals with them. But, before entering on this research, I shall call your attention to a few preliminaries which come before us at the threshold.
