One of the world’s most famous scientists just came out in favor of legalizing marijuana.

“If you really analyze it, relative to other things that are legal, there’s no reason for it to ever have been made illegal in the system of laws,” astrophysicist Neil deGrasse Tyson said on Monday.

“Alcohol is legal and it can mess you up way more than smoking a few jays,” he added.

Tyson was responding to a Facebook Live question submitted by a MassRoots reporter about whether he agrees on cannabis policy with the late cosmologist Carl Sagan, who created the classic Cosmos TV series that the younger scientist recently hosted a reboot of.

Sagan, a well-known marijuana enthusiast, once gave a tour of Cornell University, where he taught, to Tyson. While Tyson didn’t end up enrolling there, Sagan became somewhat of a mentor during the course of his career.

Sagan, who died of pneumonia in 1996 after a battle with bone marrow cancer, used medical cannabis toward the end of his life to treat “not only the lack of appetite and the nausea [from chemotherapy] but to refocus on the beauty of life in the midst of such torture,” his widow Ann Druyan said in a 2014 interview.

But much earlier than that, he used marijuana for fun and insight.

“The cannabis experience has greatly improved my appreciation for art, a subject which I had never much appreciated before,” Sagan wrote in a pseudonymous 1969 essay under the name Mr. X. “I am convinced that there are genuine and valid levels of perception available with cannabis (and probably with other drugs) which are, through the defects of our society and our educational system, unavailable to us without such drugs.”

Sagan wasn’t especially publicly vocal about the legalization debate during his lifetime, but he did follow it closely. An examination of his private papers at the Library of Congress unearthed numerous letters and documents on the topic.

“How much money is spent every year on the planet on illegal drugs?” he wrote in one letter in 1990. “Does the existence of such enormous amounts of money inevitably lead to corruption in police and military enforcement agencies, legislators, intelligence agencies and the Executive branch? If the financial rewards from drug dealing are so enormous, will not the suppression of the drug industry in one nation cause it to proliferate in another nation?”

While it’s not known if Tyson has personal experience with marijuana, he did make clear in 2015 that he never indulged in it with Sagan.

“The times I met him I don’t think he was high,” he said during an interview with actress Susan Sarandon during an episode of his StarTalk TV show. “He was channeling the universe, as good educators will do, and so if that was the consequence of a marijuana-induced perspective I would not have known it at the time.”

Earlier that year Tyson said during a Reddit “Ask Me Anything” session that he personally feels sobriety is the best path to enlightenment and good decision making.

“If you’re in an altered state, you can think something is good that you just created, but it really isn’t,” he said. “For me, the least altered state of awareness I can achieve is the one that I seek, because that one is most likely to be closest to reality.”

So while Tyson seems to disagree with Sagan on marijuana’s ability to generate insights, we now know he is at least on the same page when it comes to cannabis’s legal status.