Quote Interpretation

Maybe I'm being simplistic, but the meaning seems clear to me: that "ethical values" cannot be subject to the hypothetico-deductive methods of science since ethics requires socially negotiated value judgements. Taking the single example of eugenics illustrates the point. i.e. there may be "scientific indications" that the selective breeding of humans may eliminate various diseases etc, but WW2 was fought partially on the grounds of putting a stop to the Nazi regime's pursuit of such a principle.

As a footnote, we might bear in mind that Kant attempted a "scientific approach" (i.e. the application of logic/reason) to ethics with his advocating of "the categorical imperative", and although influential, it remains debatable.