"In transgressing the law of nature, the offender declares himself to live by another rule than that of reason and common equity" Ch.2, 8 - John Locke

I doubt not, but from self-evident Propositions, by necessary Consequences, as incontestable as those in Mathematics, the measures of right and wrong might be made out.

we see how labour could make men distinct titles to several parcels of it, for their private uses; wherein there could be no doubt of right, no room for quarrel.

You must do nothing before him, which you would not have him imitate. If any thing escape you, which you would have pass as a fault in him, he will be sure to shelter himself under your example, and shelter himself so as that it will not be easy to come at him, to correct it in him the right way.