INTRODUCTION. 17

to dialectic. It is remarkable (see above) that this personal conception of mind is confined to the human mind and is not, as at p. 22 C, extended to the divine. (4) If we may be allowed to interpret one dialogue of Plato by another, the sciences of figure and number are probably classed with the arts and true opinions because they proceed from hypotheses (compare Republic 511). (5) The mention of a sixth class is merely due to the quotation from Orpheus; that Plato had no intention of filling up this class with the "necessary pleasures" or anything else is evident from the brief recapitulation that follows (67 A), in which he speaks of pleasure as holding the fifth rank.

VI. We may now endeavor to ascertain the relationship of the Philebus to the other dialogues. Here appears the same polemic against the "ideas" that is carried further in the Parmenides and the Sophist. The principle of the "one and many" of which he speaks here is illustrated by examples in the Sophist and Politicus. Notwithstanding the differences of style, many resemblances may be noticed between the Philebus and Gorgias. The theory of the simultaneousness of pleasure and pain is common to both; there is also a common tendency to take up arms against pleasure, although the view of the Philebus, which is probably the later of the two, is the more moderate. At 46 A, B, there seems to be an allusion to the passage in the Gorgias (494) in which Socrates dilates on the pleasures of itching and scratching. Nor is there any real discrepancy in the manner in which Gorgias and his art are spoken of in the two dialogues. For Socrates, at p. 58, is far from implying that the art of rhetoric has a real sphere of practical usefulness; he only means that the refutation of the claims of Gorgias is not necessary for his present purpose. He is saying, in effect: "Admit, if you please, that rhetoric is the greatest and most useful of sciences—this does not prove that dialectic is not the purest and most exact." From the Sophist and Politicus, we know that his hostility toward the sophists and rhetoricians was not mitigated in later life, and yet both in the Politicus and Laws he admits of a higher use of rhetoric.

Reasons have been already given for assigning a late date to the Philebus. That the date is probably later than that of the Republic may be further argued on the following grounds: 1. The general resemblance to the later dialogues and to the Laws. 2. The more complete account of the nature of good and pleasure. 3. The distinction between