The mathematical theory of probability was unknown until that time and you can see that insurance suddenly made an appearance at that time.

在那之前,概率的数学理论,是不存在的,而随着概率论的出现,保险业也突然出现了

耶鲁公开课 - 金融市场课程节选

In the second lecture, I talked about the pooling of risks and the basic theme of that lecture was that we now have a mathematical theory, probability theory.

第二课，我讲了风险汇聚及分摊,那节课的主题是,一门数学理论，即概率论。

耶鲁公开课 - 金融市场课程节选