.... possible. Respond to any question of theirs with a non-sequitur if you can manage it. If there are too many of them in your branch of the workplace, quietly lobby for a reassignment, without citing the stupids as a reason. If all of this forces you to do the stupid's job completely for him (at least for a time), do so without complaint. All of that is much better than having to converse or reason with a stupid person.

Point is, if you meet any stupid anywhere, RUN. If you can. They are more dangerous than the evil people (who are generally pretty predictable). But stupids will randomly do or say things that will kill you and everyone around them (potentially).

If you can't run from a stupid and you're trapped there, you have to marginalize the stupid any way possible -- and in an unobtrusive manner such that the marginalization is kind of hard to detect (or attack).

BTW, I haven't met any real stupids amongst the onc RNs or MDs I know. They'd never make it this far. There are some stupids in other various positions though, and I try to stay out of their way.