You can't teach old dogs new tricks, and you can't teach Attorney General Jeff Sessions to stop freaking out about marijuana, according to Seth Rogen. The stoner comedy icon says there's hope for America to repeal marijuana prohibition someday, but there's no hope of convincing Sessions that cannabis isn't actually as bad as heroin.

"You can't convince a crazy person not to be crazy," Rogen told Rolling Stone recently. "[S]ome people still live in a place where they believe all the propaganda that was put out there to control people who were smoking weed, who at that time were largely minority people. It's all fake. Sessions probably believes his own bullshit. If he doesn't believe it, he's just fucking saying it because he's like a crusty old white dude that wants to uphold the war on drugs, probably because he's racist."

Rogen also took a shot at former House Speaker John Boehner for joining the cannabis industry after stonewalling marijuana reform for decades.

"All that shows is that motherfucker likes money and that's it," Rogen said. "He doesn't give a shit about anything else other than fucking money and someone showed that guy a piece of paper that said, 'Hey, if you stop trying to put people in jail for weed and instead support it, you will make this much money' and he went, 'Fuck it.'"

But despite the grumpy tone of those responses, Rogen is especially upbeat about the state of cannabis politics now that Canada has voted to legalize cannabis nationwide. "I can't wait to go back to Canada," he eagerly told Stephen Colbert on Friday. Check out the full interview - including Rogen's takedown of House Speaker Paul Ryan - in this clip: