Over lunch yesterday, Bryan Caplan explained to me some finer points of standard libertarian legal philosophy. Here is my current understanding (errors mine of course): Libertarians believe: Each human is endowed with property in his or her own body, and can obtain property in other physical objects, including land, via certain “making” processes. People can trade such property rights via explicit contracts. It is not morally permitted to violate property rights as determined by current contracts, except to defend or retaliate against other violations. Contract violations can happen via “fraud” (= lies) that create deviations between a contract’s words and deeds. (If a contract specifies damages for breach, it is not immoral to breach if you pay the specified damages.) There is more to morality, and within these constraints people should use their property to achieve such other morality.