For a finite-size flow system to persist in time (to live), its configuration must evolve in such a way that provides easier access to the currents that flow through it.
Everything that moves, is a flow system. The constructal law dictates that flow systems should evolve over time, acquiring better and better configurations to provide more access for the currents that flow through them.
Life is movement and the constant morphing of the design of this movement. To be alive is to keep on flowing and morphing. When a system stops flowing and morphing, it is dead.
Flow systems configure and reconfigure themselves over time. This evolution occurs in one direction: Flow design get measurably better, moving more easily and farther if possible. Of course there will be bumps and mistakes: Every trial involves error. But in broad terms, tomorrow's system should flow better than today's.
The constructal law teaches us that nothing operates in isolation. every flow system is part of a bigger flow system, shaped by and in service to the world around it.
Living is motion, and motion is change and alteration and therefor the alternative to motion is un-mothion, stasis, death.