I have a friend who thinks if I don't renounce Evolution I will turn into a Nazi. Can you please explain why modern Science no longer considers eugenics to be a viable model?

I think it's safe to say that your friend has a deeply misguided logic, and I can safely add that you are at no risk of turning into a Nazi on the basis of accepting the theory of evolution.

Unfortunately the links between Nazism and evolution are artificially drawn in order too seemingly discredit evolution, but the argument has no basis in logic, and is a nonsensical and outdated approach that is continually dredged up again and again.

The most recent resurgence of this argument has followed the release of a pithy, poorly researched, polemic documentary called 'Expelled',  in the USA last year. Fortunately, a good website called Expelled exposed was produced by the National Centre for Science Education to counter the many flawed arguments, including the one you cite.

Last edited by Jim Caryl (28th Jan 2010 02:43:34)

I would add that eugenics isn't actually that closely linked to either evolution or Nazism, despite what you might hear. Eugenics is essentially an application of selective breeding to human beings, and farmers were carrying out selective breeding of plants and animals long before evolutionary theory came along. And the idea of eugenics was popular to some extent not just with the Nazis, but with people in many countries who thought it would be a good way to literally improve humanity.

As for why eugenics is no longer considered viable... well, the reasons are as much political as scientific. Scientifically, there are limits to what selective breeding and even genetic engineering can accomplish, especially in any reasonable time frame. Changing traits like body size might be fairly trivial, but anything that might be seen as a real "improvement" would likely prove elusive. Probably the best that could be hoped for would be the elimination, after a very long time, of some congenital disorders from the genepool. However, even that would involve major restrictions on human freedom, in that people with the "wrong" genes would have to be prevented from reproducing. This brings up the political side of things - just because something is scientifically possible doesn't mean that governments will ever permit it to be done.

Finally, even if evolutionary theory HAD been a major source of inspiration for the Nazis - which of course isn't true, as Jim pointed out - that would have absolutely no bearing on the correctness of the theory. It would still have to be judged based on the evidence from nature.

I would just like to add that Hitler actually ordered Darwin's works to be burned.  He wrote a very long book, called Mein Kampf which makes not a single reference to Darwin.
The University of Arizona has a list of books that the Nazis wanted to have destroyed
http://www.library.arizona.edu/exhibits … uments.htm
The relationship between evolution and the Nazis is simply an attempt, as Jim says, to make evolution seem bad by associating it with Nazi ideology, for which there is no evidence.