How Many Ph.D.'s does it Take to Screw in a Lightbulb?

We are back from a somewhat stressful holiday whose highlights included Vietnamese food with La Rebelde and dinner at ABQ's famous Flying Star with M&R . Happily, our Landlord is in town visiting his mom, a professor emeritus, and was available to do some repairs. We have been living in what nephew Asher calls "darkaness" ever since the ceiling lights in our dining room conked out for the second time. Last time this happened, the Landlord had to replace a failed dimmer switch, and we were disappointed that the new switch hadn't lasted longer. He agreed that perhaps installing a conventional on/off switch would be best. When we returned home from dinner last night, however, we found a note on the dining room table saying, "Dear Pete-n-Lo: Coincidentally the light bulbs all burned out at the same time. I have replaced them for you and will get to the cold frame soon." We didn't even think to try new light bulbs.

So how many Ph.D.'s does it take to screw in a lightbulb? I guess three. Two to recognize that the old light bulbs don't light and one to raise the guy who can actually screw them in. The image is from here.