"First Law" is a science fiction story by Isaac Asimov.
First law may also refer to:
Newton's first law of motion First law of thermodynamics First law of crystallography Mendel's first law of segregation Tikanga Māori, the law of the Maori
See also Second law (disambiguation) Third law (disambiguation) The First Law, a fantasy series by Joe Abercrombie The First Law (film), a 1918 silent film Three Laws of Robotics