  There are at least two ways to deduce Einstein's field equations from the
principle of maximum force $c^4/4G$ or from the equivalent principle of maximum
power $c^5/4G$. Tests in gravitational wave astronomy, cosmology, and numerical
gravitation confirm the two principles. Apparent paradoxes about the limits can
all be resolved. Several related bounds arise. The limits illuminate the
beauty, consistency and simplicity of general relativity from an unusual
perspective.
