Imagine a fantasy world that’s exactly as the world is today except that two things are missing: alcohol and marijuana. And then imagine that tomorrow, both of them are discovered. What happens now? How are each of them used – and, perhaps more importantly, regulated? How would we weigh the relative benefits and costs of alcohol versus marijuana?

That’s the topic of our latest podcast, “What’s More Dangerous: Marijuana or Alcohol?” (You can subscribe to the podcast at iTunes, get the RSS feed, or listen via the media player above. You can also read the transcript, which includes credits for the music you’ll hear in the episode.)

As simple a question as this may be, it isn’t so easy to answer empirically. That’s because alcohol is legal, widely available, relatively cheap, and for the most part society smiles upon it — whereas marijuana is generally illegal, less easily available, and often frowned upon. This, of course, is changing, as more places are legalizing marijuana (Colorado and Washington State in the U.S.; Portugal, meanwhile, decriminalized many drugs not long ago.) That said, there is a lot more data on alcohol use than marijuana use, simply because of alcohol’s prevalence.

Working within these limitations, we do our best to address the question of whether alcohol or marijuana is “more dangerous.” Along the way, you’ll hear Steve Levitt‘s views on the relationship between alcohol and crime. Harvard economist Jeffrey Miron tells us whether prohibition works, and whether the long-standing belief in marijuana as a gateway drug is legitimate. And you’ll hear from the British psychiatrist David Nutt, a one-time “drug czar” who was fired for criticizing the British government’s decision to reclassify marijuana as a more serious drug. Nutt had come to believe that alcohol (and cigarettes) are, on balance, more dangerous than marijuana and other drugs. He and his colleagues calculated the “harm score” of various drugs, taking into account everything from physical damage to lost productivity. As you can see here, alcohol came out at the very top — in large part, to be sure, because of its prevalence:

Nutt is, however, realistic about the everlasting appeal of alcohol:

NUTT: Most of my professional career, I have been trying to find ways of treating alcoholism and helping people deal with the problems of alcohol dependence and alcohol withdrawal, and trying to find an antidote to alcohol. And I realize now that’s impossible. And it occurred to me a while back that maybe we’re asking the wrong question — rather than try to solve the problem of alcohol, why don’t we find an alternative to alcohol which doesn’t cause problems. Find a safe alternative, a drug which makes you pleasantly intoxicated, but which does not cause addiction, does not rot your brain, your liver or your guts, etc.

That’s why Nutt and his colleagues have been working on a synthetic alcohol product, as well as an alcohol antidote, a “sober pill”: