A lecture about English
A linguistics professor was lecturing to his English class one day. "In English," he said, "A double negative forms a positive. In some languages, though, such as Russian, a double negative is still a negative. However, there is no language wherein a double positive can form a negative."

A voice from the back of the room piped up, "Yeah, right."

Atheist professor
An atheist professor was teaching a college class and he told the class that he was going to prove that there was no God.

He said, "God if you are real, then I want you to knock me off this platform. I'll give you 15 minutes!"

Ten minutes went by. He kept taunting God, saying, "Here I am God, I'm still waiting." He got down to the last couple of minutes and a big 240-pound football player happened to
walk by the door and heard what the professor said.

The football player walked into the classroom and in the last minute, hit the professor full force, sending him flying off the platform.

The professor got up, obviously shaken, and said, "Where did
you come from, and why did you do that?"

The football player replied, "God was busy; He sent me!"