Republican presidential candidate Dr. Ben Carson, who is consistently polling second to frontrunner Donald Trump, spoke yesterday to hundreds of potential voters in San Francisco at an event hosted by the Commonwealth Club of California.

“I know there are a lot of people who say ‘overwhelming science,’ but then when you ask them to show the overwhelming science, they never can show it,” Carson, a retired neurosurgeon, said in an interview with the San Francisco Chronicle after the event. “There is no overwhelming science that the things that are going on are man-caused and not naturally caused.”

“Gimme a break,” he added.

Carson has previously described the issue of climate change as “irrelevant.”