"I think we must quote whenever we feel that the allusion is interesting or helpful or amusing"

In this quote, Cliff Fadiman is expressing his belief that it is important to utilize quotations whenever they add value to a conversation or piece of writing. He recommends that quotes need to be used when they are interesting, valuable, or amusing. This suggests that quotes should not be utilized just for the sake of utilizing them, but rather ought to serve a purpose in improving the general message or tone. Fadiman's words likewise suggest that quotations can be an effective tool in communication, as they can add depth, humor, or insight to a subject. In general, this quote highlights the importance of thoughtful and purposeful use of quotes in our language and writing.