Question

Hello Rabbi, since I’ve seen that the Rabbi often mentions Kant’s approach to morality, I thought I’d ask something on that topic:
There is an important and very interesting article by Dr. Israel Eldad from the period of the Eichmann trial, may his name be blotted out, which draws a direct line between the Kantian conception of morality (and “pure reason”) and the outcome of Nazism. Could the Rabbi explain a bit more about Kant’s categorical imperative and why such an approach might give legitimacy to phenomena like these?
 
Thank you in advance