Courtesy increases, as we travel eastward round the world, coincidently with a decrease in the sense of self.

Asia is more courteous than Europe, Europe than America.

Particular races show the same concomitance of characteristics.

France, the most impersonal nation of Europe, is at the same time the most polite.
Considered a priori, the connection between the two is not far to seek.
Impersonality, by lessening the interest in one's self, induces one to take an interest in others.

Introspection tends to make of man a solitary animal, the absence of it a social one.