You've never seen a black swan.

你从没见过黑色的天鹅
So, you end up going through life assuming that

于是你从生活中得出结论
there are no black swans.

黑色的天鹅是不存在的
But, in fact, there are

但事实上它们是存在的
and you might finally see one.

而且你看到了一只
You don't want to predicate making complicated gambles

你不会将赌注
under the assumption that they don't exist.

押在不可能存在的东西上
Talib, who's a Wall Street professional,

华尔街的专家塔利博
talks about these black swans as being the real story of finance.

用金融界的真实案例讨论黑天鹅现象
Now. I want to move away from statistics

好的讲到这里我将离开统计学
and talk about present values,

讨论一下现值
which is another concept in finance that is fundamental.

这是金融学中的另一个基本概念