"“Logically, developing children are carefully screened for physical and mental defects before being allowed to mature.” Baley interrupted. “You mean you kill them if they don’t—” “If they don’t measure up. Quite painlessly, I assure you. The notion shocks you, just as the Earthman’s uncontrolled breeding shocks us.”"
January 1, 1970
https://en.wikiquote.org/wiki/Isaac_Asimov