This paper is about change. It is about changes in the way we think about knowledge and the kinds of knowledge teachers need to teach well. The change I will address is the shift from episteme to phronesis and from phronesis to artistry. Episteme is a term that represented, for the ancient Greeks, the discovery of knowledge; but not just any kind of knowledge. Episteme refers to what Greek philosophers regarded as true and certain knowledge. For the Greeks, to have episteme, what one believed to be the case needed to actually be the case. Put another way, if you knew something, that is, if you really knew something, it had to be true. False knowledge was for the Greeks an oxymoron.