There was a school of thinkers who called into question the very possibility of knowledge. These were the sceptics.
Scepticism, as a doctrine of the schools, was first proclaimed by Pyrrho of Elis (365-275) BCE, who was in Alexander's army, and campaigned with it as far as India. It seems that this gave him a sufficient taste of travel, and. that he spent the rest of his life in his native city, Elis, where he died in 275 B.C. There was not much that was new in his doctrine, beyond a certain systematizing and formalizing of older doubts. Scepticism with regard to the senses had troubled Greek philosophers from a very early stage; the only exceptions were those who, like Parmenides and Plato, denied the cognitive value of perception, and made their denial into an opportunity for an intellectual dogmatism. The Sophists, notably Protagoras and Gorgias, had been led by the ambiguities and. apparent contradictions of sense-perception to a subjectivism not unlike Hume's. Pyrrho seems (for he very wisely wrote no books) to have added moral and logical scepticism to scepticism as to the senses. He is said to have maintained that there could never be any rational. ground for preferring one course of action to another. In practice, this meant that one conformed to the customs of whatever countryone inhabited. A modern disciple would go to church on Sundays and. perform the correct genuflexions, but without any of the religious beliefs that are supposed to inspire these actions. Ancient Sceptics went through the whole pagan ritual, and were even sometimes priests; their Scepticism assured them that this behaviour could not be proved wrong, and their common sense (which survived their philosophy) assured them that it was convenient.
Scepticism naturally made an appeal to many unphilosophic minds. People observed the diversity of schools and the acerbity of their disputes, and decided that all alike were pretending to knowledge which was in fact unattainable. Scepticism was a lazy man's consolation, since it showed the ignorant to be as wise as the reputed men of learning. To men who, by temperament, required a gospel, it might seem unsatisfying, but like every doctrine of the Hellenistic period it recommended itself as an antidote to worry. Why trouble about the future? It is wholly uncertain. You may as well enjoy the present; "What's to come is still unsure." For these reasons, Scepticism enjoyed a considerable popular success.
It should be observed that Scepticism as a philosophy is not merely doubt, but what may be called dogmatic doubt. The man of science says "I think it is so-and-so, but I am not sure." The man of intellectual curiosity says "I don't know how it is, but I hope to find out." The philosophical Sceptic says "nobody knows, and nobody ever can know." It is this element of dogmatism that makes the system vulnerable. Sceptics, of course, deny that they assert the impossibility of knowledge dogmatically, but their denials are not very convincing.
Pyrrho's disciple Timon, however, advanced some intellectual arguments which, from the standpoint of Greek logic, were very hard to answer. The only logic admitted by the Greeks was deductive, and all deduction had to start, like Euclid, from general principles regarded as selfevident. Timon denied the possibility of finding such principles. Everything, therefore, will have to be proved by means of something else, and all argument will be either circular or an endless chain hanging from nothing. In either case nothing can be proved. This argument, as we can see, cut at the root of the Aristotelian philosophy which dominated the Middle Ages.
Some forms of Scepticism which, in our own day, are advocated by men who are by no means wholly sceptical, had not occurred to the Sceptics of antiquity. They did not doubt phenomena, or question propositions which, in their opinion, only expressed what we know directly concerning phenomena. Most of Timon's work is lost, but two surviving fragments will illustrate this point. One says "The phenomenon is always valid." The other says: "That honey is sweet I refuse to assert; that it appears sweet, I fully grant." A modern Sceptic would point out that the phenomenon merely occurs, and is not either valid or invalid; what is valid or invalid must be a statement, and no statement can be so closely linked to the phenomenon as to be incapable of falsehood. For the same reason, he would say that the statement "honey appears sweet" is only highly.
Timon lived at Athens throughout the later years of his long life, and died there in 235 B.C. With his death, the school of Pyrrho, as a school, came to an end, but his doctrines, somewhat modified, were taken up, strange as it may seem, by the Academy, which represented the Platonic tradition.
The manner in which Arcesilaus taught would have had much to commend it, if the young men who learnt from him had been able to avoid being paralysed by it. He maintained no thesis, but would refute any thesis set up by a pupil. Sometimes he would himself advance two contradictory propositions on successive occasions, showing how to argue convincingly in favour of either. A pupil sufficiently vigourous to rebel might have learnt dexterity and the avoidance of fallacies; in fact, none seem to have learnt anything except cleverness and indifference to truth. So great was the influence of Arcesilaus that the Academy remained sceptical for about two hundred years.
In the middle of this sceptical period, an amusing incident occurred. Carneades, a worthy successor of Arcesilaus as head of the Academy, was one of three philosophers sent by Athens on a diplomatic mission to Rome in the year 156 B.C. He saw no reason why his ambassadorial dignity should interfere with the main chance, so he announced a course of lectures in Rome. The young men, who, at that time, were anxious to ape Greek manners and acquire Greek culture, flocked to hear him. His first lecture expounded the views of Aristotle and Plato on justice, and was thoroughly edifying. His second, however, was concerned in refuting all that he had said in his first, not with a view to establishing opposite conclusions, but merely to show that every conclusion is unwarranted. Plato's Socrates had argued that to inflict injustice was a greater evil to the perpetrator than to suffer it. Carneades, in his second lecture, treated this contention with scorn. Great States, he pointed out, had become great by unjust aggressions against their weaker neighbours; in Rome, this could not well be denied. In a shipwreck, you may save your life at the expense of some one weaker, and you are a fool if you do not. "Women and children first," he seems to think, is not a maxim that leads to personal survival. What would you do if you were flying from a victorious enemy, you had lost your horse, but you found a wounded comrade on a horse? If you were sensible, you would drag him off and seize his horse, whatever justice might ordain. All this not very edifying argumentation is surprising in a nominal follower of Plato, but it seems to have pleased the modern-minded Roman youths.
There was one man whom it did not please and that was the elder Cato, who represented the stern, stiff, stupid, and brutal moral code by means of which Rome had defeated Carthage. From youth to old age, he lived simply, rose early, practised severe manual labour, ate only coarse food, and never wore a gown that cost over a hundred pence. Towards the State he was scrupulously honest, avoiding all bribery and plunder. He exacted of other Romans all the virtues that he practised himself, and asserted that to accuse and pursue the wicked was the best thing an honest man could do. He enforced, as far as he could, the old Roman severity of manners: " Cato put out of the Senate also, one Manilius, who was in great towardness to have been made Consul the next year following, only because he kissed his wife too lovingly in the day time, and before his daughter: and reproving him for it, he told him, his wife never kissed him, but when it thundered."
Scepticism, however, did not disappear. It was revived by the Cretan Aenesidemus, who came from Knossos, where, for aught we know, there may have been Sceptics two thousand years earlier, entertaining dissolute courtiers with doubts as to the divinity of the mistress of animals. The date of Aenesidemus is uncertain. He threw over the doctrines on probability advocated by Carneades, and reverted to the earliest forms of Scepticism. His influence was considerable; he was followed by the poet Lucian in the second century A.D., and also, slightly later, by Sextus Empiricus, the only Sceptic philosopher of antiquity whose works survive. There is, for example, a short treatise, "Arguments Against Belief in a God," translated by Edwyn Bevan in his Later Greek Religion, pp. 52-56, and said by him to be probably taken by Sextus Empiricus from Carneades, as reported by Clitomachus.
This treatise begins by explaining that, in behaviour, the Sceptics are orthodox: "We sceptics follow in practice the way of the world, but without holding any opinion about it. We speak of the Gods as existing and offer worship to the Gods and say that they exercise providence, but in saying this we express no belief, and avoid the rashness of the dogmatisers."
He then argues that people differ as to the nature of God; for instance, some think Him corporeal, some incorporeal. Since we have no experience of Him, we cannot know His attributes. The existence of God is not self-evident, and therefore needs proof. There is a somewhat confused argument to show that no such proof is possible. He next takes up the problem of evil, and concludes with the words: "Those who affirm positively that God exists cannot avoid falling into an impiety. For if they say that God controls everything, they make Him the author of evil things; if, on the other hand, they say that He controls some things only, or that He controls nothing, they are compelled to make God either grudging or impotent, and to do that is quite obviously an impiety."
Scepticism, while it continued to appeal to some cultivated individuals until somewhere in the third century A.D., was contrary to the temper of the age, which was turning more and more to dogmatic religion and doctrines of salvation. Scepticism had enough force to make educated men dissatisfied with the State religions, but it had nothing positive, even in the purely intellectual sphere, to offer in their place. From the Renaissance onwards, theological scepticism has been supplemented, in most of its advocates, by an enthusiastic belief in science, but in antiquity there was no such supplement to doubt. Without answering the arguments of the Sceptics, the ancient world turned aside from them. The Olympians being discredited, the way was left clear for an invasion of oriental religions, which competed for the favour of the superstitious until the triumph of Christianity.
Sextus describes the sceptic as one who is committed to investigation, not as one who arrives at and advocates set doctrines. Accordingly sceptics do not offer teachings, but stick to their enquiries; they conform to the appearance of things in the sense that they act on what they perceive, they accept traditions and customs and live accordingly, they obey the promptings of nature in the matter of hunger and thirst, and they acquire
practical skills – such as medicine – but they do not claim to know or strive to know, and they do not assert but merely report how things seem, like a chronicler or historian who simply records what happens.
Latin translations of Sextus’ writings were published in the mid-sixteenth century CE and had a great influence on the rise of modern philosophy, not least on Montaigne, Descartes, Pascal, Bayle, Hume and other thinkers of the Enlightenment, and thence to more recent and contemporary philosophy where philosophical scepticism continues to motivate efforts at constructing epistemological theories which either answer or embrace sceptical considerations.
