I have a gag reflex for Social Darwinism.

Social Darwinism is one of the most repulsive and offensive ideas ever created/supported.

It is based on the notion that the world is just and people are inherently good. The world is in fact not just. And goodness is easily tainted by the stink of greed. 

Truth: the world is not just.

The only way to believe that the world is just is to be so blind and naive as to believe racism and sexism does not permeate every aspect of our society and drastically bind people's abilities. It is to misunderstand that because some people have advanced beyond the confines of their circumstances that all people are able to which is a horrible misconception. Some people come out of completely vegetative states, most don't, but I bet they would if they could. Do you think women appreciate the oppression they face? The constant attacks on their bodies, their rights, and their health? Do you think people of color appreciate attacks on their livelihood, history, and rights? No. They do not. To believe the world is just is to benefit from the unacknowledged privilege that they have and profit from greatly. But to acknowledge it would mean being aware of it and to be aware of it would be to feel guilt for it and most likely to try to resolve. And who would want to lose the perks they have had all throughout their history. 

Everyone is not starting from the same place. Imagine playing monopoly where you come into the game two hours late and the rules are rigged against you. There is only so much money and for someone else to get richer, you have to get poorer. A concept that society has yet to grasp. As every millionaire and corporation gets richer, there is some person, some business, some country (yes, country... please research the effects of the IMF and World Bank...shit research Nike or OshKosh... on the two-thirds world) is getting poorer. 

So to say that only the prosperous and intelligent should reproduce is to be diseased by the notion of fairness and equality and to be completely blind to the privilege one possesses. It is the most offensive notion created. Intelligence is not a universal concept and cannot be truly operationally defined without bias. Those who are rich and "intelligent" should not necessarily reproduce. And those who are poor and may struggle obtaining an education should not be prevented from reproducing. Being poor or illiterate is not a reflection of your life-fitness, it is a primarily a reflection of the social conditions you were raised in and the oppression you faced. But what would a rich, white male (aka the people who have created and been the puppet master in perpetuating this notion) who has never had anything but the optimal social conditions know or understand about that.