Democritus quotes - page 3
There are two forms of knowledge, one genuine, one obscure. To the obscure belong all of the following: sight, hearing, smell, taste, feeling. The other form is the genuine, and is quite distinct from this. [And then distinguishing the genuine from the obscure, he continues:] Whenever the obscure [way of knowing] has reached the minimum sensibile of hearing, smell, taste, and touch, and when the investigation must be carried farther into that which is still finer, then arises the genuine way of knowing, which has a finer organ of thought.
Democritus