INTRODUCTION.

Knowledge; and from this reasoning, neither that which is to know nor that which is to be known can exist. original Greek: "γνῶσις· καὶ ἐκ τούτου τοῦ λόγου οὔτε τὸ γνωσόμενον οὔτε τὸ γνωσθησόμενον ἂν εἴη." Cratylus 440 A.

Thus the teaching of Herakleitos A philosopher famous for the idea that "everything flows" and change is the only constant. tends to one inevitable end—none can know, for nothing can be known.

Parmenides.

§ 6. Seeing then that Becoming The process of change and movement. and Multitude The variety of many different things in the world. are unknowable, are we therefore forced to abandon in despair all striving after knowledge? Or is it perchance possible that there exists Being or Unity, which abides for ever sure and can be really and certainly known? Such at least was the conviction of Parmenides.

This great philosopher, who may be considered as the earliest herald of the idealism The philosophical view that reality is mentally constructed or based on ideas rather than material things. which should come but yet was not, set about his work by a method widely different from that of the Ionian physicists¹. The Ionians indeed, and even Herakleitos himself, in a certain sense sought unity, inasmuch as they postulated one single element as the substrate The underlying substance. of material phenomena. But such a unity could not content Parmenides. What, he may have asked, do we gain by such a unity? If there is one element underlying the appearances of material nature, why choose one of its manifestations as the fundamental form in preference to another? If the same substance appears now as fire, now as air, now as water, what is the use of saying that fire, air, or water is the ultimate element? And if with Anaximandros we affirm that the ultimate substance is an undefined unlimited substrate, this is only as much as to say, we do not know the substrate of things. In any case the supposition of a material substrate leaves us just where we were. The unity that pervades nature must be one of a totally different sort; not a material element which is transformed into multitudinous semblances, but a principle, a formative essence, distinct from the endless variety of visible nature. It must be no ever-changing substrate, but an essence simple, immutable, and eternal, far removed from the ken of sensation and to be reached by reason alone. And not only must it be verily existent, it must be the sum-total of existence; else would it fail of its own nature and fall short of itself. Since then the One is and is the whole, it must needs follow that the Many are not at all. Material nature then, with all her processes and appearances, is utterly non-existent, a vain delusion of the senses: she is Not-being, and Not-being exists in no wise—only Being is. And since

¹ I take Parmenides as the representative of Eleatic thought, regarding Xenophanes as not, properly speaking, a philosopher at all, and Zeno as merely developing one aspect of Parmenidean teaching.