Add Bill Maher to the growing list of comedians who think political correctness is bad for comedy -- and are making an issue of it.

Maher spoke with comedian Jeff Ross on "Real Time" over the weekend about Jerry Seinfeld, who said last week he doesn't play at colleges because they're too PC. Maher suggested the reason was political.

"I used to fight with this audience all the time, because we used to get the audience strictly from liberal sources, then we got the audience like from everywhere and I've had a much better time the last couple of months," he said.

Ross called comedy "medicine." "You don't want it watered down; you want it potent," he said. "We have a responsibility to shine a light on the darkest aspects of society."