The Harm Principle, proposed by J.S. Mill in his essay On Liberty, is as good a bumper-sticker sized moral philsophy as you’re going to get. That being said, it’s woefully inadequate, and certainly no less so in the Wiccan formulation.
I mean, just dealing with harm for the moment, suppose you take it to heart that so long as you do no harm, you should be allowed to do as you like. So now all we need is a good rule for what counts as harm. When you’ve worked that out, for extra credit you can try and fit it on a bumper sticker.
Of course, the mantra only mentions doing harm. It doesn’t deal with whether it’s okay to allow harm. But if you think it’s okay to allow harm to come to others so long as you’re not the one doing it, then I guess that’s not an issue for you.
Let’s move on to some of the other classic normative principles of ethics:
Principle of Personal Benefit – Many see it as a universal principle of ethics that one should acknowledge the extent to which an action benefits oneself. Do you believe that we are under no obligation to admit what’s in it for us?
Principle of Social Benefit – Obviously we will admit to how society benefits from our own actions, but are we obliged to admit any such thing about other people? Our adversaries, even?
Principle of Benevolence – Do you think we should help others? This is not covered under “An ye do no harm, do as ye will.”
Principle of Honesty – Should everybody be free to lie, so long as their lies don’t count as harm by the clear and simple definition you came up with in the above excercise?
Arguably, all of this stuff and more comes out when you unpack the notion of harm, making the rede about as useful an adequate a moral guide as “be good.”