The article below reproduces some portions and revises other portions of the previous article.

The problems of authority, law and order, obligation, and self-interest first became central topics of speculation in the thought of the Sophists, in the late fifth and early fourth centuries BCE. The most famous Sophists stressed the distinction between nature (physis) and convention (nomos), and they put laws in the latter category. They generally attributed law to human invention and justified obedience to law only to the extent that it promoted one's own advantage. Laws were artificial, arrived at by consent; most acts that were just according to the law were contrary to nature; the advantages laid down by the law were chains upon nature, but those laid down by nature were free.

In the time of the Sophists notions of law, justice, religion...