Pyrrho, who probably no more believed in books than in anything else, never committed his opinions to writing; and what we know of them is derived from the reports of his disciples, which, again, are only preserved in a very incomplete form by the compilers of the empire. According to these, Pyrrho began by declaring that the philosophic problem might be summed up in the three following questions: ‘What is the nature of things? What should be our relation to them? What is the practical consequence of this determination?’ Of its kind, this statement is probably the best ever framed, and might be accepted with equal readiness by every school of thought. But the scepticism of Pyrrho at once reveals itself in his answer to the first question. We know nothing about things in themselves. Every assertion made respecting them is liable to be contradicted, and neither of the two opposing propositions deserves more credence than the other. The considerations by which Pyrrho attempts to establish this proposition were probably suggested by the systems of Plato and Aristotle. The only possible avenues of communication with the external world are, he tells us, sense and reason. Of these the former was so universally discredited that he seems to have regarded any elaborate refutation of its claims as superfluous. What we perceive by our senses is the appearance, not the reality of things. This is exactly what the Cyrenaics had already maintained. The inadequacy of reason is proved by a more original method. Had men any settled principles of judgment, they would agree on questions of conduct, for it is with regard to these that they are best informed, whereas the great variety of laws and customs shows that the exact opposite is true. They are more hopelessly divided on points of morality than on any other.[227] It will be remembered that Pyrrho’s fellow-townsman, Hippias, had, about a hundred years earlier, founded his theory of Natural Law on the arbitrary and variable character of custom. The result of combining his principles with those professed by Protagoras and Gorgias was to establish complete moral scepticism; but it would be a mistake to suppose that moral distinctions had no value for him personally, or that they were neglected in his public teaching.