At a campaign event in Des Moines, Iowa on Thursday, Dr. Ben Carson joked about the flash drive California Gov. Jerry Brown sent to him, containing reports on climate change.

“A couple weeks ago I was getting a lot of press. ‘Jerry Brown sends Carson his memos about global warming to educate him’ and all this crap you know,” Carson told the crowd. “I don’t need any education about the environment.”

Environmentalists try “to get all kinds of unreasonable things through without looking at the evidence,” he said. He suggested the best approach is “to find the cleanest most environmentally friendly way to do things” by teaming up with business interests, industry and academia.