Thomas Hobbes Quote
For the Lawes of Nature (as Justice, Equity, Modesty, Mercy, and (in summe)doing to others, as wee would be done to,) of themselves, without the terrour of some Power, to cause them to be observed, are contrary to our naturall Passions, that carry us to Partiality, Pride, Revenge, and the like. And Covenants, without the Sword, are but Words, and of no strength to secure a man at all.
The Second Part, Chapter 17, p. 85. - Leviathan (1651)