The thesis then becomes that people are addicted to substances because they are cut off from the world. That it's not a physical addiction in the way we previously imagined.

It's interesting, what people call psychological addiction actually stems from real, physical changes in the brain that alters the way you behave. It's a lot more than just a craving. This is why psychiatrists consider addiction a disease, it changes your motivation so greatly that addicts will continue to seek out drugs even though they know and understand that their addiction is negatively impacting their life.

That's my problem with drug laws in the context of addiction, it's like punishing a person with Tourette's for swearing in public. Maybe trying drugs for the first time is a choice but once you're addicted it's a lot more complicated, and considering a lot of people addicted to things like heroin started on prescription painkillers, how is the fact they use illegal drugs even their fault?

I'm an advocate of total legalisation of a few drugs from each class and decriminalisation of the rest. For example, legalising cannabis but not spice would probably reduce spice use more than legalising both.