There's traditionally been two different ways of seeing addiction. Either it's a sin and you're a horrible bad person and you are just choosing to be hedonist or it's a chronic progressive disease. And while I certainly believe addiction is a medical problem that should be dealt with by the health system, the way we've conceptualized addiction as a disease is not actually accurate, and it has unfortunately become stigmatizing and it's also created a lot of hopelessness in a lot of people.

I know that sounds really extreme, but if you just look at the history, you will find Harry Anslinger [first U.S. commissioner of the Bureau of Narcotics] going on about satanic swing and how reefer will make black people think they're as good as white people - which to him, obviously, was a very horrible outcome. This is the basis of our drug laws.

A lot of addiction actually ends by age 30 - something like 50 percent of all addictions with the exception of tobacco - and I think a lot of what's going on there is that the self-control areas of the brain are finally developed enough to be able to stop yourself from relapsing or just continuing. There is a maturational aspect to it as well.

A lot of the stuff that we say about drugs is just wrong.

The best outcomes that are seen for therapy intervention and for other psychological interventions is where the therapist really connects and the person really feels understood. That matters often even more than the technique.

We have a system that was devised by racists to create racist ends.

Marijuana is not not harmful, but is the least harmful psychoactive substance that we have, with the possible exception of caffeine.