Human beings have a natural and innate need to bond, and when we're happy and healthy, we'll bond and connect with each other, but if you can't do that, because you're traumatized or isolated or beaten down by life, you will bond with something that will give you some sense of relief. Now, that might be gambling, that might be pornography, that might be cocaine, that might be cannabis, but you will bond and connect with something because that's our nature. That's what we want as human beings.

You get a rat and you put it in a cage, and you give it two water bottles: One is just water, and the other is water laced with either heroin or cocaine. The rat will almost always prefer the drug water and almost always kill itself quite quickly.

Professor Alexander built a cage that he called "Rat Park," which is basically heaven for rats. Crucially, they've got loads of friends in there.  

 In Rat Park, they don't like the drug water. None of them ever use it compulsively oroverdose. You go from almost 100% overdose when they're isolated to 0% overdose when they have connected lives.