Does it have to be a light bulb? 'Cause I had this other idea...
Why would a blind man need a light bulb?
Two. One to identify that the lightbulb has indeed burned out, and one to call the maintenence man to change the lightbulb.
Just one but every time he does he causes a blackout.
It only takes two mice to screw in a light bulb. The hard part is getting them in there.
The pirate responds, "arrr! I've no idea, but it's drivin' me nuts!"
They have no idea what 12 inches actually looks like. I for some reason could not find a way to phrase this any better. Credit to my coworker.
Adobe.