Buddhist tradition calls this samvega :

“the oppressive sense of shock, dismay, and alienation that come with realizing the futility and meaninglessness of life as it’s normally lived; a chastening sense of our own complacency and foolishness in having let ourselves live so blindly; and an anxious sense of urgency in trying to find a way out of the meaningless cycle. This is a cluster of feelings that we’ve all experienced at one time or another in the process of growing up, but I don’t know of a single English term that adequately covers all three. It would be useful to have such a term, and maybe that’s reason enough for simply adopting the word samvega into our language.”

[via a rather disappointing thread at Metafilter]

Thoughts That, If Not Deep, Are At Least Wide