Cometh the hour, cometh the man. I don't know who said this proverb first. There is something like it in Matthew and Luke, though the passages clearly refer to Jesus. But the way it has come down to us is what may be called the optimist's version of history.
It means that at crucial moments, a courageous leader will come forth to guarantee his nation's future - like Irish nationalist Michael Collins, who travelled to London to secure Ireland's independence, and Anwar Sadat, who made his fateful trip to Jerusalem to make peace with the Israelis.
I can't think of an exact equivalent of a cynic or realist's version of the proverb. But there is something like it; when commenting on the revolutions of 1848, the British historian AJP Taylor famously wrote: "German history reached its turning point and failed to turn."
Great historians work on the minutest devilish details to extract universal lessons. As Harvard economic historian Niall Ferguson said, Taylor's comment on Germany is applicable to most countries in most years.
In the same article, Ferguson made fun of journalists - who "have surely reported nine out of the last five revolutions".
But it does not seem an exaggeration to report that Hong Kong is reaching a turning point, a democratic transition, if not a revolution. Either we aim for full democracy, which is only possible if those who truly believe in it dare to pursue rapprochement with Beijing and develop a workable relationship based on trust and mutual respect.