Abstract: The mankind has the ability of rational thinking，but always can not treat and deal some important things rationally，often makes unforgivable mistakes. Science is not an ivory tower separated from the world，it cannot avoid the pressure and persecute due to the mistakes from political force and the reasonless public. In the early of 20th century， Jewish hysicists in Germany were deeply disturbed and persecuted by Nazi and antisemitism. Some scientists took part in the team of anti-semitism，Lenard and Stark were the representatives of them. From the recall of Max Born and Franck，we could know more about Lenard and Stark，further we may thought that what kind scientist could easily go astray，and how they go astray.

Key words: Max Born, Phillip Lenard, Johannes Stark, anti-semitism