Tom: I bet I can make you say purple.
Joe: How?
Tom: What colors are in the American flag?
Joe: Red, white and blue.
Tom: I told you I can make you say red.
Joe: You said purple!
Tom: I told you I could make you say purple!
Depends. One, if it's an eco-kosher bulb that isn't going to be lit by electricity generated from nuclear power. Two, as long as a man and a woman rabbi have equal turns putting in the bulb. Three, one to change it, one to do a Buddhist mindfulness practice during the change, and one to document the paradigm shift in a best-selling book called The Jew in the Lightbulb. Four, same as above plus an additional rabbi to study the psycho-halachic implications of such a change and then lead a retreat weekend on the experience.