  Two ways to deduce the equivalence of the field equations of general
relativity and the principle of maximum force $c^4/4G$ - or the equivalent
maximum power $c^5/4G$ - are presented. A simple deduction of inverse square
gravity directly from maximum force arises. Recent apparent counterarguments
are refuted. New tests of the principle in astronomy, cosmology,
electrodynamics, numerical gravitation and quantum gravity are proposed.
