This is the site where you can read this most poignant work of Chesterton, "Eugenics and Other Evils."
I am sure you will probably have a hard time finding it anywhere else today, as it deals with topics the liberal left would probably rather we stupidly accept and champion like dolts. It also makes some very good points about the kinds of laws that lead to atrocities like we saw in German history. Worth a read, because of it's timeless truths!
Eugenics and Other Evils