Nor need we seriously consider whether Plato was right in assuming that an animal so various could not be confined within the limits of a single definition. In the infancy of logic, men sought only to obtain a definition of an unknown or uncertain term; the after reflection scarcely occurred to them that the word might have several senses, which shaded off into one another, and were not capable of being comprehended in a single notion. There is no trace of this reflection in Plato. But neither is there any reason to think, even if the reflection had occurred to him, that he would have been deterred from carrying on the war with weapons fair or unfair against the outlaw Sophist.

III. The puzzle about 'Not-being' appears to us to be one of the most unreal difficulties of ancient philosophy. We cannot understand the attitude of mind which could imagine that falsehood had no existence, if reality was denied to Not-being: How could such a question arise at all, much less become of serious importance? The answer to this, and to nearly all other difficulties of early Greek philosophy, is to be sought for in the history of ideas, and the answer is only unsatisfactory because our knowledge is defective. In the passage from the world of sense and imagination and common language to that of opinion and reflection the human mind was exposed to many dangers, and often

On the other hand, the discovery of abstractions was the great source of all mental improvement in after ages. It was the pushing aside of the old, the revelation of the new. But each one of the company of abstractions, if we may speak in the metaphorical language of Plato, became in turn the tyrant of the mind, the dominant idea, which would allow no other to have a share in the throne. This is especially true of the Eleatic philosophy: while the absoluteness of Being was asserted in every form of language, the sensible world and all the phenomena of experience were comprehended under Not-being. Nor was any difficulty or perplexity thus created, so long as the mind, lost in the contemplation of Being, asked no more questions, and never thought of applying the categories of Being or Not-being to mind or opinion or practical life.

But the negative as well as the positive idea had sunk deep into the intellect of man. The effect of the paradoxes of Zeno extended far beyond the Eleatic circle. And now an unforeseen consequence began to arise. If the Many were not, if all things were names of the One, and nothing could be predicated of any other thing, how could truth be distinguished from falsehood? The Eleatic philosopher would have replied that Being is alone true. But mankind had got beyond his barren abstractions: they were beginning to analyze, to classify, to define, to ask what is the nature of knowledge, opinion, sensation. Still less could they be content with the description which Achilles gives in Homer of the man whom his soul hates—

os chi eteron men keuthe eni phresin, allo de eipe.

For their difficulty was not a practical but a metaphysical one; and their conception of falsehood was really impaired and weakened by a metaphysical illusion.

The strength of the illusion seems to lie in the alternative: If we once admit the existence of Being and Not-being, as two spheres which exclude each other, no Being or reality can be ascribed to Not-being, and therefore not to falsehood, which is the image or expression of Not-being. Falsehood is wholly false; and to speak of true falsehood, as Theaetetus does (Theaet.), is a contradiction in terms. The fallacy to us is ridiculous and transparent,—no better than those which Plato satirizes in the Euthydemus. It is a confusion of falsehood and negation, from which Plato himself is not entirely free. Instead of saying, 'This is not in accordance with facts,' 'This is proved by experience to be false,' and from such examples forming a general notion of falsehood, the mind of the Greek thinker was lost in the mazes of the Eleatic philosophy. And the greater importance which Plato attributes to this fallacy, compared with others, is due to the influence which the Eleatic philosophy exerted over him. He sees clearly to a certain extent; but he has not yet attained a complete mastery over the ideas of his predecessors—they are still ends to him, and not mere instruments of thought. They are too rough-hewn to be harmonized in a single structure, and may be compared to rocks which project or overhang in some ancient city's walls. There are many such imperfect syncretisms or eclecticisms in the history of philosophy. A modern philosopher, though emancipated from scholastic notions of essence or substance, might still be seriously affected by the abstract idea of necessity; or though accustomed, like Bacon, to criticize abstract notions, might not extend his criticism to the syllogism.

The saying or thinking the thing that is not, would be the popular definition of falsehood or error. If we were met by the Sophist's objection, the reply would probably be an appeal to experience. Ten thousands, as Homer would say (mala murioi), tell falsehoods and fall into errors. And this is Plato's reply, both in the Cratylus and Sophist. 'Theaetetus is flying,' is a sentence in form quite as grammatical as 'Theaetetus is sitting'; the difference between the two sentences is, that the one is true and the other false. But, before making this appeal to common sense, Plato propounds for our consideration a theory of the nature of the negative.

The theory is, that Not-being is relation. Not-being is the other of Being, and has as many kinds as there are differences in Being. This doctrine is the simple converse of the famous proposition of Spinoza,—not 'Omnis determinatio est negatio,' but 'Omnis negatio est determinatio';—not, All distinction is negation, but, All negation is distinction. Not-being is the unfolding or determining of Being, and is a necessary element in all other things that are. We should be careful to observe, first, that Plato does not identify Being with Not-being; he has no idea of progression by antagonism, or of the Hegelian vibration of moments: he would not have said with Heracleitus, 'All things are and are not, and become and become not.' Secondly, he has lost sight altogether of the other sense of Not-being, as the negative of Being; although he again and again recognizes the validity of the law of contradiction. Thirdly, he seems to confuse falsehood with negation. Nor is he quite consistent in regarding Not-being as one class of Being, and yet as coextensive with Being in general. Before analyzing further the topics thus suggested, we will endeavour to trace the manner in which Plato arrived at his conception of Not-being.

In all the later dialogues of Plato, the idea of mind or intelligence becomes more and more prominent. That idea which Anaxagoras employed inconsistently in the construction of the world, Plato, in the Philebus, the Sophist, and the Laws, extends to all things, attributing to Providence a care, infinitesimal as well as infinite, of all creation. The divine mind is the leading religious thought of the later works of Plato. The human mind is a sort of reflection of this, having ideas of Being, Sameness, and the like. At times they seem to be parted by a great gulf (Parmenides); at other times they have a common nature, and the light of a common intelligence.

But this ever-growing idea of mind is really irreconcilable with the abstract Pantheism of the Eleatics. To the passionate language of Parmenides, Plato replies in a strain equally passionate:—What! has not Being mind? and is not Being capable of being known? and, if this is admitted, then capable of being affected or acted upon?—in motion, then, and yet not wholly incapable of rest. Already we have been compelled to attribute opposite determinations to Being. And the answer to the difficulty about Being may be equally the answer to the difficulty about Not-being.

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