Sir David Ross's Pluralistic Theory of Duty: Prima Facie Duty Explained

[UrbanXrisis]

In Sir David Ross's Pluralistic Theory Of Duty, he talks about prima facie duty. How is prima facie duty different from just duty? I'm not sure I quite understand what prima facie duty is. Is it just a duty that stands above all other duties?

 

[NickJ]

A non-prima facie duty is a duty that one has no matter what.

A prima facie duty is a duty that one has unless and until it gets "over-ridden" by some other duty. Prima facie duties are not absolute: they are defeasible.

Example: We have a prima facie duty to not lie. But suppose we are housing a Jewish family in our secret attic and the Gestapo knocks on our door, asking whether we know the location of any Jews. We have a prima facie duty to tell the truth and not lie. But we also have a prima facie duty to protect innocent people from harm if there is no significant cost to ourselves. So our two prima facie duties are in conflict with each other. Maybe you think the duty to protect is more important, in this case, than the duty to not lie. Then the duty to not lie gets "over-ridden" (or "trumped" -- think of playing cards) by the duty to protect.

An analogy: If we're playing poker, and I lay down two pairs, to your one pair, I have a prima facie winning hand. But if someone else then lays down a full house, my prima facie winning hand gets "trumped" and is not a winning hand anymore. But if no one else had laid down a better hand, my prima facie winning hand would have been the actual winning hand.

To sum up: Prima facie duties are not absolute -- they can be over-ridden. They are "apparent" duties (prima facie = "on the face of it").