How many pessimists does it take to change a light bulb? None - it's probably screwed it too tight anyhow!
None... they live an ascetic lifestyle and prefer to not use electricity.
THAT'S *NOT* FUNNY!
None. Who do you think broke the filament in the first place
Nothing.
Two - One to put it most of the way in, and one to give it an interesting twist at the end.
Three. One to change it while the other two argue about how old the old one is.
They refuse to look at the silver lining.
The optimist sees the light at the end of the tunnel. The pessimist sees nothing. And the realist sees the train.
