Conventional Knowledge

The reason why Taoism and Zen present, at first sight, such a puzzle to the Western mind is that we have taken a restricted view of human knowledge. For us, almost all knowledge is what a Taoist would call conventional knowledge, because we do not feel that we really know anything unless we can represent it to ourselves in words, or in some other system of conventional signs such as the notations of mathematics or music.

Alan Watts in "The Way of Zen" page 24