I think the fittest will survive, but also the weakest of us should have a chance or opportunity to survive. I also think that genetic engineering (eugenics) should be used to alter the human genome, so as to make a stronger class of human beings fit to compete with each other and with artilects. I am not really for thinking of people as "worthless", I think we all have value and it can be comprised by certain decisions or natural tendencies. There is such a great diversity in the ecosystem that inequality is inherit to it. I believe the only force that should be used to stop certain traits from being passed on is the will, the choosing of the progenitor.
“Imbecility and ‘criminalistic’ tendency,” Davenport wrote, “can be traced back to the darkness of remote generations in a way that forces us to conclude that these traits have come to us directly from our animal ancestry and have never been got rid of. But now, thanks to eugenics, those traits could be “got rid of” after all, along with those who carried them." (1)
I only believe in selective breeding as chosen by free individuals, meaning no enforcement by the law requiring specific people to stop breeding (something that has been done in China for other reasons besides social Darwinism).