As for my own opinions, I think there's zero evidence that eugenics ever 'worked', in terms of an active intervention that improved the long-term genetic quality of the human race or a part of that race according to a certain defintion (except, perhaps, the Ashkenazi Jews' use of it to eradicate certain chronic forms of hereditary illness in their community). And there's even less evidence for some sort of mystical / racial / spiritual eugenics. Eventually this project will arrive at the present day and genetic modification / enhancement. On that, I'm undecided - it doesn't seem to be proven or unproven yet. I am all for it as a means to cure hereditary illnesses. But the dream of engineering a superbeing seems to me, historically, a dangerous idea.