ABSTRACT
For ancient authors, to know means to see. It is indeed vision that offers them the best example of sensory cognition. It is also vision that is supposed to be an analogue of intellectual cognition. And when the latter is divided into an intuitive and a discursive cognition, this last, according to a general opinion, cannot unfold its sequences of syllogisms so as to produce science without having its foundation in the cognition of principles, which is itself a kind of vision.
