Darwin worried about the impact of Christian concern for "the imbecile, the maimed & the sick" for this very reason. "No one who has attended to the breeding of domestic animals will doubt that this must be highly injurious to the race of man."
Darwin himself remained sufficiently the child of his Christian upbringing to find this a very distressing reflection. Others, in due course, would not...
"Homo sapiens is just another species. To insist otherwise is to cling to the shattered fragments of religious belief. Yet the implications of this view - which the Nazis, of course, claimed as their sanction for genocide - remain unsettling for many." #Dominion
"Heaven forbid."
Quite!
Quite!
The Nazis - as the Spartans had done - practised eugenics, not because they thought of themselves as the baddies, but because they thought it the right thing to do. Why do we, by & large, not think it's the right thing to do? Because we remain the children of Christianity.
So yes, 'heaven forbid' indeed...
