There was a conversation at my workplace the other day that I want to pose as a question to my readership: should a librarian ever use the phrase “I don’t know” when trying to help a library member? My position is that the phrase can be used only with a qualifier; as in, that there is a solution, advice, or suggestion as to know to find out. (For example, “I don’t know but I know someone to ask” or “I don’t know but there might be a database that has an answer”.) Only rarely that the phrase be used without additional content and only in a situation where you don’t know and you don’t even know where to begin to search. Considering the existence of impossible reference questions (insert your own experience being asked one here), I think it is a very human admission and puts you in a sympathetic position with the questioner.
The other position in the conversation was that the phrase should never be uttered, period. Any other phrase that segues into searching should be used (“Let me check on that”, etc.) but never an admission of a lack of knowledge. The idea (as I saw it) is to focus the library member on that fact that you are working to find out the answer rather than a lack of personal knowledge. (I’m probably not explaining this as well, but since it’s not my side of the argument, I’m not terribly obligated to do so.)
What do you think? Can you ever use the phrase “I don’t know”? Have you ever said it?
[Addendum: I asked my friends on the Library Society of the World Friendfeed this question earlier. You can see their responses here.]