  Rather, perhaps, the point of the argument is this: Neither “The wind in itself is cold” nor “The wind in itself is warm” is true. If we had grounds for affirming either, we would have equally good grounds for affirming both; but the conjunction “The wind in itself is cold and the wind in itself is warm” is a contradiction. This contradiction, says Protagoras, obliges us to give up all talk about “the wind in itself,” and switch to relativised talk about the wind as it seems to me or to you, etc.  (The same contradiction pushes the Plato of the Republic in the opposite direction: it leads him to place no further trust in any relativised talk, precisely because such talk cannot get us beyond such contradictions.)