Since there’s a lot of interest in my case against high-IQ misanthropy, here’s a fuller discussion from Selfish Reasons to Have More Kids:

You Don’t Have to Raise the Average to Pull Your Weight

Eighty percent of success is showing up.
– Woody Allen

When asked, “Does the birth of another baby make the world better – or worse?,” I suspect that many secretly answer, “It depends on the baby.”  If he grows up to be a scientist, they think the world’s better off.  If he grows up to be a janitor, they think the world’s worse off.  The implicit dividing line, apparently, is that people make the world a better place if and only if they raise average income.*   If our average income is $50,000 a year, the birth of a future janitor supposedly impoverishes us by pulling down the average.

To modern ears, this “eugenic” perspective sounds true but cruel – like pointing out that someone is fat or ugly.  But it’s usually not even true.  Eugenicists mistake arithmetic for injury.  A “burden on society” isn’t someone who produces less than average; it’s someone who consumes more than he produces.  The birth of a future janitor is nothing to worry about as long as he’ll be self-supporting and peaceful.  The vast majority of janitors are.

When Danny DeVito enters a room, he reduces its occupants’ average height.  But he doesn’t cause anyone to “lose height.”  Shortness isn’t contagious.  Neither is low income.  A janitor earns less than average, but his existence doesn’t impoverish his fellow citizens.

Does the world really need another janitor?  Absolutely.  If janitors weren’t useful, employers wouldn’t pay them $20,000 for a year of their time.  Many think there’s no place for unskilled workers in the high-tech economy of the future, but someone has to do their jobs.  When there aren’t enough unskilled workers to wash dishes and collect garbage, skilled workers pick up the slack – and their other talents go to waste.  If Bill Gates spent half his time cleaning his own office, making his own meals, and watching his own kids, he’d discover far fewer new ideas to enrich us all.

*  The second most-popular dividing line is probably between above- and below-average intelligence.  The famous eugenicist Karl Pearson maintained that “the sole condition under which… immigration should be allowed” is when the immigrants “form from the standpoint of intelligence a group markedly superior to our natives.”  Quoted in David Levy and Sandra Peart, “Statistical Prejudice: From Eugenics to Immigrants.”  European Journal of Political Economy 2004, p.16.