Historical parallels: Nazi propaganda dehumanized Jews as "sub-humans" and "rats"; eugenics movement called people "imbeciles"; slavery defenders used intelligence to justify treating people as less than human. Abraham Lincoln's argument against dehumanization applies directly to abortion.

Joseph Goebbels called Jews "sub-humans" and "rats." Eugenics movement (circa 1915) displayed people holding signs dehumanizing themselves. Lincoln's argument: if you enslave based on color, someone lighter can enslave you; if based on intellect, someone smarter can enslave you; if based on self-interest, they can enslave you by the same logic. None of these criteria (size, awareness, dependency, intelligence) legitimately determine human value.