natural law

noun3

1. •
   The set of universal legal or moral principles said to be discernible from nature by reason alone; one of these principles.

   • Thus, for example, it is a natural law, that he who has been the author of any damage ought to repair it. — 1850
2. •
   A law relating to natural phenomena.
3. •
   A theory describing or positing such principles.

   • Buckle […] argues that Grotius and Pufendorf understood Natural Law as a science of morals grounded in human nature. — 2007