> This kind of sensitive awareness and idealism makes them more likely to ask themselves difficult questions about the nature and purpose of their lives and the lives of those around them. They become keenly aware of their smallness in the larger picture of existence, and they feel helpless to fix the many problems that trouble them. As a result, they become depressed.

Psilocybin mushrooms have a similar effect, however ironically I have used those experiences as a way of dealing with existential depression. Rather than coming away feeling "helpless to fix the many problems" I feel more like I've shed the weight of those problems.