Creationists and advocates of intelligent design (ID) often mention the 2nd Law of Thermodynamics as a reason why evolution can’t be true. The previous link quotes the law as follows:

The entropy of an isolated system not at equilibrium will tend to increase over time, approaching a maximum value.

Their logic is that if the entropy (i.e. chaos) in a system always increases it cannot become more complex. The facts show that organisms have gotten more complex over time. This, they claim, proves that this complexity could not have evolved naturally but requires the efforts of a supernatural entity.

This is completely and provably wrong. There is no debate whatsoever in this particular line of reasoning. The reason is the word “isolated” in the above quote. The Earth is not an isolated system. There is this gigantic source of energy shining down on the Earth 24 hours per day for the last 4 billion years. It’s called the sun. When there is energy put into a system, the 2nd law of thermodynamics does not apply.

Creationists are wrong for a whole host of reasons, but they have to cross this one off their list. It makes them sound stupid. The 2nd law of thermodynamics in no way, shape or form undermines the theory of evolution.