Thus, if knowledge of things proves to be a failure, there only remains as possible an attitude of pure Scepticism; and therein is contained the answer to the second question. We know nothing whatever of the real nature of things, and hence can neither believe nor assert anything as to their nature. We cannot say of anything that it is or is not; but we must abstain from every opinion, allowing that of all which appears to us to be true, the opposite may with equal justice be true. [1407] Accordingly, all our statements (as the Cyrenaics taught) only express individual opinions, and not absolute realities. We cannot deny that things appear to be of this or the other kind; but we can never say that they are so. [1408] Even the assertion that things are of this or the other kind is not an assertion, but a confession by the individual of his state of mind. [1409] Hence, too, the universal rule of indecision cannot be taken as an established principle, but only as a confession, and, therefore, as only problematical. [1410] It must, however, remain a matter of doubt how far the captious turns of expression by which the Sceptics thought to parry the attacks of their opponents come from Pyrrho’s School. The greater part, it is clear, came into use in the struggle with the Dogmatists, and are not older than the development of the Stoic theory of knowledge by Chrysippus, and the criticism of Carneades to which it gave rise. In this despairing of anything like certain conviction consists ἀφασία, ἀκαταληψία, or ἐποχὴ, the withholding of judgment or state of indecision which Pyrrho and Timon regard as the only true attitude in speculation, [1411] and from which the whole School derived its distinctive name. [1412] [(3) Mental imperturbability.]