A History of Philosophy in Epitome

by Albert Schwegler

In the first Socratic period the Platonic philosophizing became ripe and ready for the reception of Eleatic and Pythagorean categories. To grapple by means of these categories with the higher questions of philosophy, and so to free the Socratic philosophy from its so close connection with practical life, was the task of the second period.

The Second Period—the dialectic or the Megaric—is marked externally, by a less prominence of form and poetic contemplation, and not unfrequently indeed, by obscurity and difficulties of style, and internally, by the attempt to give a satisfactory mediation for the Eleatic doctrine and a dialectic foundation for the doctrine of ideas.

By his exile at Megara, and his journeys to Italy, Plato became acquainted with other and opposing philosophical directions, from which he must now separate himself in order to elevate the Socratic doctrine to its true significance. It was now that he first learned to know the philosophic theories of the earlier sages, for whose study the necessary means could not at that period, so wanting in literary publicity, be found at Athens. By his separation from these varying standpoints, as his older fellow pupils had already striven to do, he attempted striding over the narrow limits of ethical philosophizing, to reach the final ground of knowing, and to carry out the art of forming conceptions as brought forward by Socrates, to a science of conceptions, i. e. to the doctrine of ideas. That all human acting depends upon knowing, and that all thinking depends upon the conception, were results to which Plato might already have attained through the scientific generalization of the Socratic doctrine itself, but now to bring this Socratic wisdom within the circle of speculative thinking, to establish dialectically that the conception in its simple unity is that which abides in the change of phenomena, to disclose the fundamental principles of knowledge which had been evaded by Socrates, to grasp the scientific theories of the opposers direct in their scientific grounds, and follow them out in all their ramifications,—this is the problem which the Megaric family of dialogues attempts to solve.

The Theatætus stands at the head of this group. This is chiefly directed against the Protagorean theory of knowledge, against the identification of the thinking and the sensible perception, or against the claim of an objective relativity of all knowledge. As the Gorgias before it had sought to establish the independent being of the ethical, so does the Theatætus ascending from the ethical to the theoretical, endeavor to prove an independent being and objective reality for the logical conceptions which lie at the ground of all representation and thinking, in a word, to prove the objectivity of truth, the fact that there lies a province of thought immanent in the thinking and independent of the perceptions of the senses. These conceptions, whose objective reality is thus affirmed, are those of a species, likeness and unlikeness, sameness and difference, &c.

The Theatætus is followed by the trilogy of the Sophist, the Statesman, and the Philosopher, which completes the Megaric group of dialogues. The first of these dialogues examines the conception of appearance, that is of the not-being, the last (for which the Parmenides may be taken) the conception of being. Both dialogues are especially directed to the Eleatic doctrine. After Plato had recognized the conception in its simple unity as that which abides in the change of phenomena, his attention was naturally turned towards the Eleatics, who in an opposite way had attained the similar result that in unity consists all true substantiality, and to multiplicity as such no true being belongs. In order more easily on the one side to carry out this fundamental thought of the Eleatic to its legitimate result, in which the Megarians had already preceded him, he was obliged to give a metaphysical substance to his abstract conceptions of species, i. e. ideas. But on the other side, he could not agree with the inflexibility and exclusiveness of the Eleatic unity, unless he would wholly sacrifice the multiplicity of things; he was rather obliged to attempt to show by a dialectic development of the Eleatic principle that the one must be at the same time a totality, organically connected, and embracing multiplicity in itself. This double relation to the Eleatic principle is carried out by the Sophist and the Parmenides; by the former polemically against the Eleatic doctrine, in that it proves the being of the appearance or the not-being, and by the latter pacifically, in that it analyzes the Eleatic one by its own logical consequences into many. The inner progress of the doctrine of Ideas in the Megaric group of dialogues is therefore this, viz., that the Theatætus, in opposition to the Heraclitico-Protagorean theory of the absolute becoming, affirms the objective and independent reality of ideas, and the Sophist shows their reciprocal relation and combining qualities, while the Parmenides in fine exhibits their whole dialectic completeness with their relation to the phenomenal world.

The Third Period begins with the return of the philosopher to his native city. It unites the completeness of form belonging to the first with the profounder characteristical content belonging to the second. The memories of his youthful years seem at this time to have risen anew before the soul of Plato, and to have imparted again to his literary activity the long lost freshness and fulness of that period, while at the same time his abode in foreign lands, and especially his acquaintance with the Pythagorean philosophy, had greatly enriched his mind with a store of images and ideals. This reviving of old memories is seen in the fact that the writings of this group return with fondness to the personality of Socrates, and represent in a certain degree the whole philosophy of Plato as the exaltation of the doctrine and the ideal embodiment of the historical character of his early master. In opposition to both of the first two periods, the third is marked externally by an excess of the mythical form connected with the growing influence of Pythagoreanism in this period, and internally by the application of the doctrine of ideas to the concrete spheres of psychology, ethics and natural science. That ideas possess objective reality, and are the foundation of all essentiality and truth, while the phenomena of the sensible world are only copies of these, was a theory whose vindication was no longer attempted, but which was presupposed as already proved, and as forming a dialectical basis for the pursuit of the different branches of science. With this was connected a tendency to unite the hitherto separate branches of science into a systematic whole, as well as to mould together the previous philosophical directions, and show the inner application of the Socratic philosophy for ethics, of the Eleatic for dialectics, and the Pythagorean for physics.

Upon this standpoint, the Phædrus, Plato’s inaugural to his labors in the Academy, together with the Symposium, which is closely connected with it, attempts to subject the rhetorical theory and practice of their time to a thorough criticism, in order to show in opposition to this theory and practice, that the fixedness and stability of a true scientific principle could only be attained by grounding every thing on the idea. On the same standpoint the Phædon attempts to prove the immortality of the soul from the doctrine of ideas; the Philebus to bring out the conception of pleasure and of the highest good; the Republic to develop the essence of the state, and the Timæus that of nature.

Having thus sketched the inner development of the Platonic philosophy, we now turn to a systematic statement of its principles.

III.—Classification of the Platonic System.—The philosophy of Plato, as left by himself, is without a systematic statement, and has no comprehensive principle of classification. He has given us only the history of his thinking, the statement of his philosophical development; we are therefore limited in reference to his classification of philosophy to simple intimations. Accordingly, some have divided the Platonic system into theoretical and practical science, and others into a philosophy of the good, the beautiful and the true. Another classification, which has some support in old records, is more correct. Some of the ancients say that Plato was the first to unite in one whole the scattered philosophical elements of the earlier sages, and so to obtain for philosophy the three parts, logic, physics, and ethics. The more accurate statement is given by Sextus Empiricus, that Plato has laid the foundation for this threefold division of philosophy, but that it was first expressly recognized and affirmed by his scholars, Xenocrates and Aristotle. The Platonic system may, however, without difficulty, be divided into these three parts. True, there are many dialogues which mingle together in different proportions the logical, the ethical, and the physical element, and though even where Plato treats of some special discipline, the three are suffered constantly to interpenetrate each other, still there are some dialogues in which this fundamental scheme can be clearly recognized. It cannot be mistaken that the Timæus has predominantly a physical, and the Republic as decidedly an ethical element, and if the dialectic is expressly represented in no separate dialogue, yet does the whole Megaric group pursue the common end of bringing out the conception of science and its true object, being, and is, therefore, in its content decidedly dialectical. Plato must have been led to this threefold division by even the earlier development of philosophy, and though Xenocrates does not clearly see it, yet since Aristotle presupposes it as universally admitted, we need not scruple to make it the basis on which to represent the Platonic system.

The order which these different parts should take, Plato himself has not declared. Manifestly, however, dialectics should have the first place as the ground of all philosophy, since Plato uniformly directs that every philosophical investigation should begin with accurately determining the idea (Phæd. p. 99. Phædr. p. 237), while he subsequently examines all the concrete spheres of science on the standpoint of the doctrine of ideas. The relative position of the other two parts is not so clear. Since, however, the physics culminates in the ethics, and the ethics, on the other hand, has for its basis physical investigations into the ensouling power in nature, we may assign to physics the former place of the two.