I think the best rule for life that I know of and that can apply to anyone is "love your neighbor as yourself": treat each person you run into as you'd like to

I think the best rule for life that I know of and that can apply to anyone is "love your neighbor as yourself": treat each person you run into as you'd like to be treated yourself, and when you're making decisions that will affect others (like users of your product) treat them like you'd want to be treated in your decisions. Zooming out a bit, yes it is hard to know what's good for humanity as a whole. But I'd venture to say that the most valuable asset by far towards this end is the truth - get that at any cost.