You could get a thousand recovering heroin addicts to implore this guy to spare himself the rest of the hellish journey on which he has embarked.
It wouldn't alter his course, because like all liberals, he knows what's best.
You can never make an addicted person give up what's killing them. Only rigorous self honesty can do that. But not everyone is capable of being honest to themselves. Some can and some can't. My guess is this guy is a stone cold liar. He'll be found dead with a needle in his arm at some point.