Mr.Major says it is imperative for the inquiry to determine whether Blair's cabinet knew that there were serious doubts about whether there actually were any weapons of mass destruction in the weeks and months ahead of the invasion.

VOA: standard.2010.01.02

All right, this is actually a very old piece of imperative knowledge for computing square roots, it's attributed to Heron of Alexandria, although I believe that the Babylonians are suspected of knowing it beforehand.

好，这是一个很古老的,关于计算平方根的程序性知识，是亚历山大的海伦提出的，不过我怀疑在那之前,巴比伦人就已经猜想过了。

麻省理工公开课 - 计算机科学及编程导论课程节选