The second Law of Thermodynamics is pretty clear about it: The entropy of a system not in equilibrium will tend to increase over time. (Entropy may be thought of as disorder or randomness). But, consider the history of Earth: It is a system that started out as a semi-molten mess. Later, it cooled and developed life, and it made those pesky structured organisms that went on to populate the seas and produce our jungles and forests. Then came those advanced animals that fashioned everything, even cities. Cities are much more ordered than jungles and so their entropy is lower.
Entropy(cities) < Entropy(jungles) < Entropy(molten mess). So, what's going on? How did we manage to violate the law? Are we somehow miraculously, divinely above the rules?

See The Solution	Submitted by Steven Lord
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The definition of the 2nd law in the problem was missing one detail.  The system must be "closed", i.e. have no source of energy that can be input from the outside.  The earth is not a closed system, as the sun exists to supply energy that can be used to "cause" the transition from less to more "order", or, reduce the entropy.

Interestingly, the solar system is more or less a closed system, so long as other stars and outside sources of energy stay far away.  So the solar system will eventually, as a whole system, revert to the greatest entropy.  Even as the earth becomes a small pocket of reduced entropy due to life evolving and technology advancing, the nuclear "running down" of the sun, and cooling of the other planets create far more entropy than that.  Therefore the entire system doe tend towards maximum entropy.

Posted by Kenny M on 2018-07-09 18:02:24