Whether working over practice questions in a test booklet, reading an instructional manual or an obscure book for pleasure in a library corner, we are engaging with the words and ideas of others and measuring them for their value, use and relevance. Thinking is never done in total isolation anyway but rather is always a social exercise and activity. The best teaching and learning then, I think, allows us to consider knowledge, from the most practical to the most abstract, as both social exercise and activity. This means, as exercise, that we get comfortable with the necessary repetitions of learning--reading and writing, listening and speaking with consideration. As social activity, strong teaching and learning allows us to consider knowledge production as constantly unfolding, knowledge production as a place where self-expression and communication within a larger community are not only welcome but of absolute necessity.