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Second Law of Thermodynamics
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Definition: The "Second Law of Thermodynamics" plays a common role in debates regarding evolution and creationism, but mostly because supporters of creationism don't understand what it means, even though they really think they do.

According to the 2LoT, every isolated system will eventually reach "thermal equilibrium," in which energy is not transferred from one part of the system to another. This is a state of maximum entropy where there is no order, no life and nothing happening. According to creationists, this means that everything is gradually running down and, hence, science proves that evolution cannot happen. How? Because evolution represents an increase in order, and that contadicts thermodynamics.

What these creationists fail to understand, however, is that there are two key words in the above definition: "isolated" and "eventually." The 2LoT only applies to isolated systems - to be isolated, a system cannot exchange energy or matter with any other system. Such a system will eventually reach thermal equilibrium. Now, is the earth an isolated system? No, there is a constant influx of energy from the sun. Will the earth, as part of the universe, eventually reach thermal equilibrium? Apparently - but in the mean time, portions of the universe do not have to constantly "wind down." The 2LoT is not violated when non-isolated systems decrease in entropy. The 2LoT is also not violated when portions of an isolated system (as our planet is a portion of the universe) temporarily decrease in entropy.

Also Known As: Second Law, 2LoT

Alternate Spellings: none

Common Misspellings: none

Related Resources:

Evolution & Creationism...
Is evolution a science? Is creationism a science? What is science? Is there evidence for either? Religious fundamentalists often attack evolution, but rarely from a positions of really understanding what evolution is and how it works. This FAQ will not only teach you more about the nature of evolution and evolutionary theory, but it will also explain some of the more common complaints and where they go wrong.

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