Aristotle has just finished explaining how the presence of contraries could indicate that the meaning of a term is different. Now he continues his discussion of the second tool by showing that the presence of intermediates can also do this. He explains this in Topics, Book 1.
Further, see in regard to their intermediates, if one use has an intermediate, while another has none, or if both have one but not the same one, as e.g. clear and obscure in the case of colours have grey as an intermediate, whereas in the case of sound they have none, or, if they have, it is muffled, as some people say that a muffled sound is intermediate. Clear, then, is homonymous, and likewise also obscure.
See, moreover, if some of them have more than one intermediate, while others have but one, as is the case with clear and obscure- for in the case of colours there are numbers of intermediates, whereas in regard to sound there is but one, viz. muffled.
We can also determine if a word has a different meaning by determining whether or not it has the same word for in-between that word and the contrary. Aristotles examples are based on the meaning of words used in Greek. In English we would use different examples. For example, bitter is contrary to sweet. However, when we are speaking of taste, then something half-bitter and half-sweet is called bittersweet. If we are speaking of people, then we do not call half-bitter and half-sweet people bittersweet. We have no name for that kind of person. Sometimes, a pair of contraries may have more than one intermediate in one circumstance but not in other. There is only one sound between a clear sound and an unclear one, but an object can translucent in various colors.
Next, Aristotle discusses the way contradictories show a difference in meaning.