President Obama attacked the GOP presidential field in a speech on gas prices Thursday, portraying the candidates as “stuck in the past” and unserious about dealing with the nation’s energy problems.

Delivering his fourth speech on energy in as many weeks, Obama stressed that there’s no “silver bullet” for lowering prices and took shot after shot at “professional politicians … who are running for a certain office.”

The president called out his rivals on green energy and accused them of failing to see the future.

“They dismiss wind power,” Obama said. “They dismiss solar power. They make jokes about biofuels. They were against raising fuel standards. I guess they like gas-guzzlers. They think that’s good for our future. We’re trying to move towards the future, and they want to be stuck in the past.

“We’ve heard this kind of thinking before,” Obama said. “Let me tell you something: If some of these folks were around when Columbus set sail, they must have been founding members of the Flat Earth Society; they would not have believed that the world was round.”