What can be called "consciousness of the process of abstraction." That is, consciousness of the fact that out of a virtually infinite universe of possible things to pay attention to, we abstract only certain portions, and those portions turn out to be the ones for which we have verbal labels and categories. What we abstract, i. e., "see," and how we abstract it, or see it, or see it or think about it, is for all practical purposes inseparable from how we talk about it.

Teaching as a Subversive Activity (1969)