So the article states that Carl Hart makes a claim that 70% of drug users don't meet the criteria for being a drug addict. I'm wondering how you could even get a reliable number for this for a drug like heroin, given the stigma attached to this drug and the fact that users themselves may be in denial that they are dependent on the drug. Someone can be meeting all their obligations in life and still be struggling with a drug addiction. If asked, I would imagine a lot of high functioning addicts would say they can stop whenever they want to, they just don't want to. Anyway, I may just have to give his book a read, it sounds interesting.