Be prepared to scream with laughter!
From the 2008 additions to the philosophical lexicon (stress mine):
bernard, n. (1) (from St Bernard) A shaggy dog story. Hence bernard, v. to tell such stories in lieu of making general arguments. “The risk one takes in bernarding is that one may be outsmarted.” Also baown. the punch line of a bernard. (2) A psychotic state in which one finds it impossible to visualise a bath without a naked woman in it.
I guess this is a reference to a certain well-known philosopher who had, among other things, a fondness for the metaphor of throwing out the bath… . And of course the image of a naked woman is just very funny, isn’t it. Or not.