The urge to party - until you drop
Now that markets around the world have fallen, moralists and pundits are all complaining that no one issued warnings or did anything about it until it was too late.
People should have seen it coming miles away, they say, because it was all so obvious.
Sure, it was obvious all right - after the fact. The supercilious I-told-you-so crowd actually sounds a lot like those puritans who denounce sexual immorality because it can give you diseases; parents who condemn drug abuse but who have never got high in their life; or weekend drivers who have never driven a really powerful fast car.
Everybody saw the collapse of the US housing bubble coming, everyone who was not completely stupid, anyway.
Another bubble can pop at any time on the mainland too, but few people are leaving the party yet. Everybody sees what's coming across the border. Oh, there is always the Beijing Olympics! But what happens after that - or even before?
Imagine a great neighbourhood party that starts early but only a few beautiful people show up at first. They have all the fun and drink most of the alcohol.
It's now past midnight. More people show up after hearing about how great the party is. Some food and alcohol are left, and they still taste good. There are smooch fests by the pool, on the living room sofa and in the master bedroom. You just hook up with a beautiful woman or an incredible man. Would you leave now?
Then, a friendly neighbour rings the bell. Very politely, she asks if the guests can keep it down. 'It's late,' she whispers. Do you think anyone would pay heed, quieten down and leave?
Well, the party just gets rowdier. More newcomers arrive, and they demand a piece of the action, too.
Next, the neighbour's angry husband comes over. He doesn't ring the bell; he bangs on the door. This time he threatens to call the police, 'unless you guys chill out'.
Well, there is little chance of that, short of the host cutting off the alcohol supply. But he is not doing it because he's a drinker, too.
A few people and their friends realise it's really late; they have had their fun and know the neighbours have called 999.
But these people are always in the minority.
Some others may want to leave, but it's difficult to do so when you are enjoying it so much, or you have misplaced your wallet. (When you are highly leveraged or have just received a margin call, it's not easy to unwind a position, even if you spot a headwind coming. And wishful thinking - hoping your position will improve - does the rest.)
If you're already going with the flow, you might as well stay and enjoy the rest of the night, though you will probably lose your shirt at some point.
Sure enough, several serious-looking police officers show up. It's crunch time; the party's over.
They make some arrests and kick everyone out. The host then finds out how rowdy the crowd has been. All the furniture has been smashed, the toilets and sinks are blocked and the pool is filled with rubbish. Imagine the cleanup bill!
Some wit, quoted in Charles Kindleberger's very essential Manias, Panics, and Crashes: A History of Financial Crises, says something to the effect that sometimes, you just have to join a mad crowd.
Many people must have read the story about Isaac Newton and his South Sea stocks, so I won't repeat it here. Readers can easily look it up on the internet, anyway. Newton wasn't stupid; he was a supreme genius for the ages.
But the father of classical physics was human, too. Warning about bubbles is beside the point; it never works because it is not how human nature works.
Even if every investor were as smart as Einstein or Newton, we would still have an endless cycle of bubbles and busts. Everyone, even Newton, wants to party.
Alex Lo is a senior writer at the Post