It is thus, at first sight, obvious that it was a higher and more comprehensive science than the art of deduction. For it was directed to the discovery and establishment of First Principles. Its sole object was the discovery of truth. His dialectic was an analytical and inductive method. "In Dialectic Science," says Alcinous, "there is a dividing and a defining, and an analyzing, and, moreover, that which is inductive and syllogistic." [562] Even Bacon, who is usually styled "the Father of the Inductive method," and who, too often, speaks disparagingly of Plato, is constrained to admit that he followed the inductive method. "An induction such as will be of advantage for the invention and demonstration of Arts and Sciences must distinguish the essential nature of things (naturam) by proper rejections and exclusions, and then after as many of these negatives as are sufficient, by comprising, above all (super), the positives. Up to this time this had not been done, nor even attempted, except by Plato alone, who, in order to attain his definitions and ideas, has used, to a certain extent, the method of Induction." [563]
[Footnote 562: ][ (return) ] "Introduction to the Doctrines of Plato," vol. vi. p. 249. "The Platonic Method was the method of induction."--Cousin's "History of Philosophy," vol. i. p. 307.
[Footnote 563: ][ (return) ] "Novum Organum," vol. i. p. 105.
The process of investigation adopted by Plato thus corresponds with the inductive method of modern times, with this simple difference, that Bacon conducted science into the world of matter, whilst Plato directed it to the world of mind. The dialectic of Plato aimed at the discovery of the "laws of thought;" the modern inductive philosophy aims at the discovery of the "laws of nature." The latter concerns itself chiefly with the inquiry after the "causes" of material phenomena; the former concerned itself with the inquiry after the "first principles" of all knowledge and of all existence. Both processes are, therefore, carried on by interrogation. The analysis which seeks for a law of nature proceeds by the interrogation of nature. The analysis of Plato proceeds by the interrogation of mind, in order to discover the fundamental ideas which lie at the basis of all cognition, which determine all our processes of thought, and which, in their final analysis, reveal the REAL BEING, which is the ground and explanation of all existence.
Now the fact that such an inquiry has originated in the human mind, and that it can not rest satisfied without some solution, is conclusive evidence that the mind has an instinctive belief, a proleptic anticipation, that such knowledge can be attained. There must unquestionably be some mental initiative which is the motive and guide to all philosophical inquiry. We must have some well-grounded conviction, some à priori belief, some pre-cognition "ad intentionem ejus quod quæritur," [564] which determines the direction of our thinking. The mind does not go to work aimlessly; it asks a specific question; it demands the "whence" and the "why" of that which is. Neither does it go to work unfurnished with any guiding principles. That which impels the mind to a determinate act of thinking is the possession of a knowledge which is different from, and independent of, the process of thinking itself. "A rational anticipation is, then, the ground of the prudens quæstio --"the forethought query, which, in fact, is the prior half of the knowledge sought." [565] If the mind inquire after "laws," and "causes," and "reasons," and "grounds,"--the first principles of all knowledge and of all existence,--"it must have the à priori ideas of "law," and "cause," and "reason," and "being in se" which, though dimly revealed to the mind previous to the discipline of reflection, are yet unconsciously governing its spontaneous modes of thought. The whole process of induction has, then, some rational ground to proceed upon--some principles deeper than science, and more certain than demonstration, which reason contains within itself, and which induction "draws out" into clearer light.
[Footnote 564: ][ (return) ] Bacon.
[Footnote 565: ][ (return) ] Coleridge, vol. ii. p. 413.
Now this mental initiative of every process of induction is the intuitive and necessary conviction that there must be a sufficient reason why every thing exists, and why it is as it is, and not otherwise; [566] or in other words, if any thing begins to be, some thing else must be supposed [567] as the ground, and reason, and cause, and law of its existence. This "law of sufficient (or determinant) reason" [568] is the fundamental principle of all metaphysical inquiry. It is contained, at least in a negative form, in that famous maxim of ancient philosophy, "De nihilo nihil"--"Ἀδύνατον γίνεσθαί τι ἐκ µηδενὸς προϋπάρχοντος." "It is impossible for a real entity to be made or generated from nothing pre-existing;" or in other words, "nothing can be made or produced without an efficient cause." [569] This principle is also distinctly announced by Plato: "Whatever is generated, is necessarily generated from a certain αἰτίαν"--ground, reason, or cause; "for it is wholly impossible that any thing should be generated without a cause." [570]
[Footnote 566: ][ (return) ] "Phædo," § 103.
[Footnote 567: ][ (return) ] Suppono, to place under as a support, to take as a ground.