And how is he so confident it doesn't "form new illnesses," whatever that might mean?
Like I've mentioned upthread, I've known a number of people who have clearly suffered from having tried LSD. Some of them will admit it was the worst decision they've ever made. Others will deny it, strongly encourage you to try it, and if you press them for how it might help you exactly they cannot explain, but there is a glimmer of anxiety and recognition that it changed them deeply in ways they are not comfortable with. And they want you to join them.
It's very chilling. It reminds me of how you'll see in some gay communities when someone contracts HIV they will compulsively spread it to as many people as possible.