Do no harm. That's it.

No excuses, no rationalisations. Do no harm, period.

To do good, only, always. How hard can that be? Well, very hard, sometimes. But like we’ve agreed: do no harm, that’s it. Actually I don’t think that’s enough. Sometimes doing no harm does not translate to doing good. Sometimes doing nothing may mean no harm has been done, but neither may good have been done. Sometimes doing nothing may actually wind up being harmful. I only know I haven’t done harm when I’m certain my inaction or action has brought about good.

So, do no harm. That’s it.