Ed, I am tired!  Anyway, I certainly did not mean to trivialize the suffering of vicitms of racism, only to say that most scientists  racist and anti-racist  have not been persecuted the way Galileo was.  Perhaps racist scientists should be.  But even here I would qualify it  not only do I not want to put some racist scientists in the US or Canada in the same category of Joseph Mengele, I think the crucial difference is precisely the social context  we live in a society based on free debate where a few scientists can be racist and they will be challenged publically and a well-informed public can make up its mind.  In the 1930s racist scientists lived in racist societies, both here and in Germany, and their work was used to justify and promote horrible things.  But today such scientists in eitehr the US or Germany can say what they want and for the most part, thanks in part to open scientific debate, and democratic societies where there is vigorous public debate in legislatures, their work has not had the same awful effect.  SR