On the whole, this discussion is one of the least satisfactory in the dialogues of Plato. While the ethical nature of pleasure is scarcely considered, and the merely physical phenomenon imperfectly analysed, too much weight is given to ideas of measure and number, as the sole principle of good. The comparison of pleasure and knowledge is really a comparison of two elements, which have no common measure, and which cannot be excluded from each other. Feeling is not opposed to knowledge, and in all consciousness there is an element of both. The most abstract kinds of knowledge are inseparable from some pleasure or pain, which accompanies the acquisition or possession of them: the student is liable to grow weary of them, and soon discovers that continuous mental energy is not granted to men. The most sensual pleasure, on the other hand, is inseparable from the consciousness of pleasure; no man can be happy who, to borrow Plato’s illustration, is leading the life of an oyster. Hence (by his own confession) the main thesis is not worth determining; the real interest lies in the incidental discussion. We can no more separate pleasure from knowledge in the “Philebus” than we can separate justice from happiness in the Republic.
IV. An interesting account is given in the “Philebus” of the rank and order of the sciences or arts, which agrees generally with the scheme of knowledge in the Sixth Book of the Republic. The chief difference is, that the position of the arts is more exactly defined. They are divided into an empirical part and a scientific part, of which the first is mere guesswork, the second is determined by rule and measure. Of the more empirical arts, music is given as an example; this, although affirmed to be necessary to human life, is depreciated. Music is regarded from a point of view entirely opposite to that of the Republic, not as a sublime science, coordinate with astronomy, but as full of doubt and conjecture. According to the standard of accuracy which is here adopted, it is rightly placed lower in the scale than carpentering, because the latter is more capable of being reduced to measure.
The theoretical element of the arts may also become a purely abstract science, when separated from matter, and is then said to be pure and unmixed. The distinction which Plato here makes seems to be the same as that between pure and applied mathematics, and may be expressed in the modern formula—science is art theoretical, art is science practical. In the reason which he gives for the superiority of the pure science of number over the mixed or applied, we can only agree with him in part. He says that the numbers which the philosopher employs are always the same, whereas the numbers which are used in practice represent different sizes or quantities. He does not see that this power of expressing different quantities by the same symbol is the characteristic and not the defect of numbers, and is due to their abstract nature;—although we admit of course what Plato seems to feel in his distinctions between pure and impure knowledge, that the imperfection of matter enters into the applications of them.
Above the other sciences, as in the Republic, towers dialectic, which is the science of eternal Being, apprehended by the purest mind and reason. The lower sciences, including the mathematical, are akin to opinion rather than to reason, and are placed together in the fourth class of goods. The relation in which they stand to dialectic is obscure in the Republic, and is not cleared up in the “Philebus.”
V. Thus far we have only attained to the vestibule or antechamber of the good; for there is a good exceeding knowledge, exceeding essence, which, like Glaucon in the Republic (Book IV 509), we find a difficulty in apprehending. This good is now to be exhibited to us under various aspects and gradations. The relative dignity of pleasure and knowledge has been determined; but they have not yet received their exact position in the scale of goods. Some difficulties occur to us in the enumeration: First, how are we to distinguish the first from the second class of goods, or the second from the third? Secondly, why is there no mention of the supreme mind? Thirdly, the nature of the fourth class. Fourthly, the meaning of the allusion to a sixth class, which is not further investigated.
(1) Plato seems to proceed in his table of goods, from the more abstract to the less abstract; from the subjective to the objective; until at the lower end of the scale we fairly descend into the region of human action and feeling. To him, the greater the abstraction the greater the truth, and he is always tending to see abstractions within abstractions; which, like the ideas in the “Parmenides,” are always appearing one behind another. Hence we find a difficulty in following him into the sphere of thought which he is seeking to attain. First in his scale of goods he places measure, in which he finds the eternal nature: this would be more naturally expressed in modern language as eternal law, and seems to be akin both to the finite and to the mind or cause, which were two of the elements in the former table. Like the supreme nature in the Timaeus, like the ideal beauty in the “Symposium” or the “Phaedrus,” or like the ideal good in the Republic, this is the absolute and unapproachable being. But this being is manifested in symmetry and beauty everywhere, in the order of nature and of mind, in the relations of men to one another. For the word “measure” he now substitutes the word “symmetry,” as if intending to express measure conceived as relation. He then proceeds to regard the good no longer in an objective form, but as the human reason seeking to
