There are, fundamentally, only two causes of the progress of the nineteenth century — the same two causes which you will find at the root of any happy, benevolent, progressive era in human history. One cause is psychological, the other existential — or: one pertains to man’s consciousness, the other to the physical conditions of his existence. The first is reason, the second is freedom. And when I say “freedom,” I do not mean poetic sloppiness, such as “freedom from want” or “freedom from fear” or “freedom from the necessity of earning a living.” I mean “freedom from compulsion — freedom from rule by physical force.” Which means: political freedom.