Earlier quoted context omitted.
Check out the history of LSD. It almost wasn't invented. They tested it on animals, and noticed "some level of disturbance" or some such, but nobody had any clue what the effects were, and nobody really cared. Then someone decided to try it on themselves. The only reason that was able to happen is because the legal and ethical restrictions were looser than they are today. In the meantime, several other such experimen…
AFAIK, Hoffman didn't really "decide to try it on himself", but accidentally got some dose through his skin because of working without gloves and felt that something is not right . I don't remember where I got that — I guess it was his autobiography or something.
It's interesting to realize that it did require human experimentation in order to discover, though. But maybe I'm flat out wrong about chemists dying through self-experimentation.
Regardless, I'll start re-checking my sources before saying anything.