A college student challenged a senior citizen, saying it was impossible for their generation to understand his.

“You grew up in a different world,” the student said. “Today we have television, jet planes, space travel, nuclear energy, computers...”

Taking advantage of a pause in the student's litany, the geezer said, “You're right. We didn't have those things when we were young, so we invented them! What are you doing for the next generation?”