In this video he talks about his experiences in college, smoking pot for the first time, then dabbling briefly in psychedelics. He had a very Shamanic experience during this time, which led him to studying medicine. Because of this dabbling he was able to see the world from an expanded point of view, and understand the role science plays in our future. He believes we need to go back to a deeper more guided approach to interacting with patients, and explore the causes – not just focus on the medical treatment.
I recommend watching this.