Sometimes, students ask a question and he/she will say "This is probably a stupid question..."
but a very wise professor who I highly regarded in my undergraduate studies set us straight the first time someone said that.
He told us, "The only stupid question is the one that's not asked."
That for us as students provided an open atmosphere where we weren't afraid to ask any question for fear it would be stupid or senseless, or whatever.
To this day, I use that same line.
