“Going to another country doesn’t make any difference. I’ve tried all that. You can’t get away from yourself by moving from one place to another. There’s nothing to that.”

Source: The Skin Map (2010), p. 83

Source: Extremely Loud and Incredibly Close

Source: 1860s, Evidence as to Man's Place in Nature (1863), Ch.2, p. 86

Variant: The most important reason for going from one place to another is to see what's in between, and they took great pleasure in doing just that.
Source: The Phantom Tollbooth

James Burgh, in The Dignity of Human Nature, Or, A Brief Account of the Certain and Established Means for Attaining the True End of Our Existence (1754); this is very widely misattributed to Mann, appearing at least as early as the publication of Thoughts Selected from the Writings of Horace Mann (1867) edited by Mary Mann.
Misattributed

Variant in other editions: Do not think of knocking out another person's brains, because he differs in opinion from you; it will be as rational to knock yourself on the head because you differ from what you thought ten years ago.
The Dignity of Human Nature (1754)

Source: Once and Always

Source: The Laundry Files, The Jennifer Morgue (2006), Chapter 4, “You’re in the Jet Set Now” (p. 75)

Bill Moyers interview (2002)
Context: I used to say that arts were talked about in the arts and leisure page. Now, why would it be arts and leisure? Why do we think that arts are leisure? Why isn't it arts and science or arts and the most important thing in your life? I think that art has become a big scarlet letter in our culture.
It's a big "A." And it says, you are an elitist, you're effete, or whatever those things... do you know what I mean? It means you don't connect. And I don't believe that. I think we've patronized our audiences long enough.
You can do things that would bring people to another place and still get someone on a very daily mundane moving level but you don't have to separate art from the masses.