The general societies of men are absolutely requisite for the subsistence of the species; and the public conveniency, which regulates morals, is inviolably established in the nature of man, and of the world, in which he lives.

The comparison, therefore, in these respects, is very imperfect.

We may only learn from it the necessity of rules, wherever men have any intercourse with each other.
They cannot even pass each other on the road without rules.

Waggoners, coachmen, and postilions have principles, by which they give the way; and these are chiefly founded on mutual ease and convenience.

Sometimes also they are arbitrary, at least dependent on a kind of capricious analogy like many of the reasonings of lawyers.
[Footnote: That the lighter machine yield to the heavier, and, in machines of the same kind, that the empty yield to the loaded; this rule is founded on convenience.