Nothing exists.
(1) If there were anything, then it would have either to be eternal or to have ocme into being. But it cannot have come into being, for neither out of Being nor out of Not-being can anything come to be. Nor can it be eternal, for if it were eternal, then it would have to be infinite. But the infinite is impossible for the following reason. It could not be in another, nor could it be in itself, therefore it would be nowhere. But what is nowhere, is nothing. (2) If there were anything, then it could not be known. For if there is knowledge of being, then what is thought must be, and Not-being could not be thought at all. In which case there could be no error, which is absurd. (3) Even if there were knowledge of being, this knowledge could not be imparted. Every sign is different from the thing signified; e.g. how could we impart knowledge of colours by word, since the ear hears tones and not colours? And how could the same representation of being be in the two persons at once, since they are different from one another? Nothing exists.
(Gorgias 483-375BC)