In practice, there are four laws of thermodynamics. Two of these are relatively unimportant when discussing theology, but the other two lead to strong implications regarding creation. For the purposes of this discussion, creationism simply means the idea that God, as opposed to mindless physics, is responsible for what we see in nature. As applied to the idea of a Creator, thermodynamics really applies at a fundamental level, not a specific level. That is, thermodynamics provides no particular evidence as to how God might have created, only that God is necessary.
How do the laws of thermodynamics provide evidence for creationism?
The first law of thermodynamics involves the conservation of energy. Most importantly, for the sake of creationism, this law states that energy can neither be created nor destroyed; it can only be changed in form or function. This means that the total energy of an isolated system is constant, neither increasing nor decreasing. This is evidence for creationism on the basis of simple logic. If no natural process can create or destroy energy, then neither the universe nor the laws of physics can explain the existence of energy. In other words, if energy is impossible to create, why does it exist? The most reasonable explanation is something, or Someone, outside of the laws of physics, and outside of the universe.
The second law of thermodynamics involves a concept known as entropy, which is more or less a measure of chaos. In technical terms, the second law says that when two systems interact, they will always tend towards a greater total entropy as they reach a state of mutual thermodynamic equilibrium. In layman's terms, energy always flows from hot to cold. This means that the natural trend of all systems is to uniform states of energy, or increasing entropy, or disorder.
The second law of thermodynamics provides evidence for creationism in several ways, but is often misunderstood and therefore misapplied. As with the first law, the concept of entropy leads to some logical conclusions about the universe. If the universe was infinitely old, it would now be in a state of maximum entropy: of total chaos. All temperatures in the universe would be equalized, and there would be nothing but a formless fuzzy oblivion. Since this is not the current state of the universe, the universe must have a finite age, and therefore a beginning. This makes it reasonable to consider the universe an "effect," not a "cause," and therefore it requires something beyond it in order to begin.
The second law is also a reasonable point to make when it comes to aspects of biology. However, this has to be done carefully. Creationists often cite the second law of thermodynamics as a reason why life on earth could not have possibly evolved from simpler to more complex forms, as this violates the principle of entropy. However, the earth is not a closed system. Just as water freezes in an ice tray, but boils on the stove, external sources of energy can alter the entropy of a system. Earth receives energy from the sun; this is, in theory, a source of energy which could alter the normal trend towards increasing entropy.
Where entropy is a valid point about creation comes more at a "felt" level than a specific level. Generally speaking, everything in the universe tends from order to disorder. When natural processes create order, they do so in either chaotic or simple ways. This is where the idea of specified complexity comes into play. The universal observation of humanity has been that the type of complexity found in life only occurs through deliberate, intentional means. All observed reversals of entropy result in something far less complex, to say the least.
In other words, while natural conditions can cause a local reversal of entropy, naturalistic (godless) evolution requires a constant, consistent trend of elements swimming against the entropic stream. This not only counters observations, it defies common sense.
The other two laws of thermodynamics have little impact on discussions of creation. The third law says that the entropy of a system tends towards zero as the temperature approaches absolute zero. That is to say that as energy is completely removed, and all molecular motion stops, the "chaos" of the system also dissolves.
The fourth law of thermodynamics is actually called the "zeroth" law, since it logically precedes the other three. This law states that two independent systems in thermodynamic equilibrium with a third system are in thermodynamic equilibrium with each other. This seems self-evident, but it allows for non-circular definitions of temperature. Prior to the early 20th century, physicists only spoke of the three laws of thermodynamics, but when this concept needed to be stated in objective terms, it was dubbed "law number zero," or the "zeroth" law of thermodynamics.
All in all, the existence of these laws, as well as their implications, gives far more weight to the idea of a creator, and to creationism, than to atheism or pure naturalism.
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