you cannot say “This is my duty but I will not do it because it may hurt my friend”, you also cannot use duty itself as an excuse to do your duty. You cannot say to your friend: “Listen, I must drop you now because it is my ethical duty. I know it hurts you but this is my duty.” Because in this way you already objectify yourself, it is not you. Kant means that duty itself is not an excuse to do your duty. You are fully responsible to formulate what your duty is.

http://ift.tt/2lkHxNV