Some of us might find adultery absolutely unacceptable and worthy of
How can one make a universal rule about this?
Would that not require a knowledge of every belief and desire
of every person?
Kant’s answer to this (at least the way Velleman seems to understand him)
People who have diverging moral views must have them for a reason
If they do not, then their actions do not have any moral basis
if they merely say, for example, “I just don’t mind adultery”, or :I just hate
adultery”, this cannot count as a reason
We can never deviate about such a thing and acting on the basis of
feelings and desires just brings us back to the state of the wanton
When we try to figure out which action is objectively right, what we
should do is try to think about possible reasons and evaluate them
The important thing is that we exclude reasons of the kind
“because that how I feel like” (which are not really reasons, or in any
case are not good reasons) and on