Nothing is more important for teaching us to understand the concepts we have than to construct fictitious ones. - Ludwig Wittgenstein

If we hear a Chinese we tend to take his speech for inarticulate gurgling. Someone who understands Chinese will recognize language in what he hears. Similarly I often cannot recognize the human being in someone etc.

Our craving for generality has [as one] source … our preoccupation with the method of science. I mean the method of reducing the explanation of natural phenomena to the smallest possible number of primitive natural laws; and, in mathematics, of unifying the treatment of different topics by using a generalization. Philosophers constantly see the method of science before their eyes, and are irresistibly tempted to ask and answer in the way science does. This tendency is the real source of metaphysics, and leads the philosopher into complete darkness. I want to say here that it can never be our job to reduce anything to anything, or to explain anything. Philosophy really is “purely descriptive.

That ∨, ⊃, etc., are not relations in the sense of right and left, etc., is obvious.