Earlier theories-- it's wonderful to have scientific theories that you can use to handle these problems, which you cannot demonstrate any fact for whatsoever.

更早些的理论...,幸好我们还有些科学理论,可以用来处理这些问题,这些没有实例,可以证明的问题

耶鲁公开课 - 古希腊历史简介课程节选