THREE:After explaining at considerable length what Being is not, Aristotle now proceeds to ascertain what it is. He tells us that just as all number qua number must be either odd or even, so all Being qua Being must have certain universal attributes. These he sets himself to discover. When Descartes long afterwards entered on a somewhat similar inquiry, he fell back on the facts of his own individual consciousness. Aristotle, on the contrary, appeals to the common consciousness of mankind as embodied in ordinary language. In how many senses do we say that a thing is? The first answer is contained in his famous Ten Categories.239 These342 are not what some have supposed them to be, summa genera of existence, but summa genera of predication. In other words, they are not a classification of things, but of the information which it is possible to receive about a single thing, more especially about the richest and most concrete thing known to usa human being. If we want to find out all about a thing we ask, What is it? Of what sort? How large? To what does it belong? Where and when can we find it? What does it do? What happens to it? And if the object of our investigations be a living thing, we may add, What are its habits and dispositions? The question has been raised, how Aristotle came to think of these ten particular categories, and a wonderful amount of rubbish has been written on the subject, while apparently no scholar could see what was staring him in the face all the time, that Aristotle got them by collecting all the simple forms of interrogation supplied by the Greek language,240 and writing out their most general expressions.We have seen how Carneades, alike in his theory of probability and in his ethical eclecticism, had departed from the extreme sceptical standpoint. His successor, Clitomachus, was content with committing the doctrines of the master to writing. A further step was taken by the next Scholarch, Philo, who is known as the Larissaean, in order to distinguish him from his more celebrated namesake, the Alexandrian Jew. This philosopher asserted that the negations of the New Academy were not to be taken as a profession of absolute scepticism, but merely as a criticism on the untenable pretensions of the Stoa. His own position was that, as a matter of fact, we have some certain knowledge of the external world, but that no logical account can be given of the process by which it is obtainedwe can only say that such an assurance has been naturally stamped on our minds.254 This is the theory of intuitions or innate ideas, still held by many persons; and, as such, it marks a return to pure Platonism, having been evidently suggested by the semi-mythological fancies of the161 Meno and the Phaedrus. With Philo as with those Scotch professors who long afterwards took up substantially the same position, the leading motive was a practical one, the necessity of placing morality on some stronger ground than that of mere probability. Neither he nor his imitators saw that if ethical principles are self-evident, they need no objective support; if they are derivative and contingent, they cannot impart to metaphysics a certainty which they do not independently possess. The return to the old Academic standpoint was completed by a much more vigorous thinker than Philo, his pupil, opponent, and eventual successor, Antiochus. So far from attempting any compromise with the Sceptics, this philosopher openly declared that they had led the school away from its true traditions; and claimed for his own teaching the merit of reproducing the original doctrine of Plato.255 In reality, he was, as Zeller has shown, an eclectic.256 It is by arguments borrowed from Stoicism that he vindicates the certainty of human knowledge. Pushing the practical postulate to its logical conclusion, he maintains, not only that we are in possession of the truth, but alsowhat Philo had deniedthat true beliefs bear on their face the evidence by which they are distinguished from illusions. Admitting that the senses are liable to error, he asserts the possibility of rectifying their mistakes, and of reasoning from a subjective impression to its objective cause. The Sceptical negation of truth he meets with the familiar argument that it is suicidal, for to be convinced that there can be no conviction is a contradiction in terms; while to argue that truth is indistinguishable from falsehood implies an illogical confidence in the validity of logical processes; besides involving the assumption that there are false appearances and that they are known to us as such, which would be impossible unless we were in a position to compare them with the corresponding162 truths.257 For his own part, Antiochus adopted without alteration the empirical theory of Chrysippus, according to which knowledge is elaborated by reflection out of the materials supplied by sense. His physics were also those of Stoicism with a slight Peripatetic admixture, but without any modification of their purely materialistic character. In ethics he remained truer to the Academic tradition, refusing to follow the Stoics in their absolute isolation of virtue from vice, and of happiness from external circumstances, involving as it did the equality of all transgressions and the worthlessness of worldly goods. But the disciples of the Porch had made such large concessions to common sense by their theories of preference and of progress, that even here there was very little left to distinguish his teaching from theirs.258
