I don't think it discusses family resemblance as such (at least, during a quick scan I didn't find the words 'family resemblance' just now), but anyone who wants to include a significant amount of Wittgenstein in an introductory logic course should try to get hold of William Brenner's "Logic and Philosophy: an integrated introduction." It was published in 1993 and so might not be readily available, but it's a very nice book and discusses Wittgenstein's work at some length. There are some references to Wittgenstein in my "Why be Good? A Historical Introduction to Ethics," but nothing like an extended discussion. I had originally intended to include more on him, but was persuaded by the publisher (in light of suggestions from people who read the first draft) to cut most of it out. This leads me to suspect that any introductory ethics book would be likely to receive the same kind of recommendation. Certainly I don't know of any such book that does say much about Wittgenstein. Duncan Richter