This increased mobility has produced a great change in the mentality of educated people - more perhaps in Europe than in America, because European travel quickly takes the traveller across frontiers and into different civilisations, while the three thousand miles from New York to Los Angeles produce less change in this respect than the twenty-one miles from Dover to Calais.
Source: "On locomotion" [From: Mortals and Others: Bertrand Russell's American Essays, 1931-1935, v.1 (1975)]
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