Referring to our "fragility of thought," the Bureau of Surrealist Research in their "Declaration of 27 January, 1925," noted "on what shifting foundations, what caverns we have built our trembling houses."
When this fragility is brought to our attention, it can make us reassess who we are and what our world is in vital ways. Because such reassessment can be such a keystone to our growth, it pays to set those houses trembling real good from time to time.
Such an experience naturally disturbs as well as enlightens, but if
you're interested in having it in a "safe" way, I would heartily
recommend a tracking down the works of Thomas Ligotti or Shaun Tan or a browse through some of the visuals from the Art Institute of Chicago's "Shatter, Rupture, Break"
exhibition, which you can see by clicking on the link above, though the show itself is unfortunately gone now. The
image below, "Eye and Barbed Wire" by Nathan Learner, is from that show
and serves as an excellent way to whet the appetite.