The obsession with running is really an obsession with the potential for more and more life.

城市是人类最伟大的发明。

The historian must be impartial, but not indifferent.

The true cost of oil isn't just the price per barrel—it's the environmental and social impact.

研究历史的人，贵在能够贯通古今的变化，探究天道与人事的关系。

我不知道我想要什么。我反复无常、不表态、被动；我喜欢不确定、无边界；我喜欢持续的不确定性。

Sustainability isn’t a trend; it’s the only way forward.