# The Second Law of Thermodynamics

Another favourite argument for God’s existence put forward by theists are those concerned with what is called the Second Law of Thermodynamics.

Before going into the two main forms of the arguments we must first familiarize ourselves with this Law as understanding it is the key to seeing the inadmissibility of these arguments for God’s existence.

The two forms of fundamentalist arguments using the Second Law are:

As we can see below, ultimately these attempts to use the second law to prove God's existence fail.

## The Second Law of Thermodynamics

The Law involves a thermodynamic quantity called entropy. This quantity, for a system, is derived from the ratio of the heat energy of a system to the highest temperature object within the system. In its very basic form entropy measures the availability of useful energy to do work. The lower the entropy the more useful energy available. Thus, to borrow a good metaphor by Philip Kitcher, entropy tells us how much energy is “locked up” or unusable in a system. [1] As the heat energy say a glass of tap water can never flow into a cup of hot coffee placed next to it, we say that the energy available in the tap water is “locked” up. Alternatively, entropy can be viewed as the measure of disorder in a system. In this case, a lower entropy implies a more ordered system . Thus a salt crystal with their atoms neatly arranged has a lower entropy than a disordered system such a gases where the atoms and molecules fly about chaotically. [2]

Having given a rough idea of what entropy is, we will now proceed to introduce the Second Law of Thermodynamics. This law states that the entropy in any closed physical process or system will always increase. In other words, a closed system will always tend to get more and more disordered over time, with less and less useful energy available. Thus a hot cup of coffee will eventually cool down to the temperature of the room, where the room and the coffee is considered a closed system. And water without any external energy (such as from a pump) will always flow downhill. A closed system is a system in which there is not energy exchange between itself and the environment surrounding it. [3]

Note the second law is not applicable to an open system; where energy exchange between the system and the surroundings occurs. An obvious example is the cooling of a room by an air-conditioner. By itself, the room will not begin to get cooler than the surroundings. The air-conditioner pumps heat out from the room allowing it to cool. If we take just the entropy of the room, we will find that the amount of heat in the room will decrease resulting in an entropy decrease. But the room is an open system since there is an exchange of energy with the outside, namely the energy that is fed into the air-conditioner. To form a closed system we must take the air-conditioner, the power supply to it and the room together. The increase in entropy caused by the conversion of energy to feed the air-conditioner will outweigh the decrease of entropy within the room. Thus when all the appropriate components of a closed system are taken into account, there will always be an entropy increase.

Similarly, the sustenance of life in itself is an example of an open system where the living being actually becomes and stays highly ordered. This is, of course, only made possible because living beings, such as human beings, have an external energy source, i.e. food, to keep it’s internal system in a highly ordered (or low entropy) state. Of course, if we consider the food, it’s energy source (ultimately the sun) and the human being, which is a closed system; the total entropy will increase with time.

## The Anti-Evolution Argument

Now what does all this have to do with God’s existence? In its first form, the theistic entropy argument states that the Second Law of Thermodynamics does not allow evolution to happen. An if evolution could not have happened, then God must have created all the living things on this world. [a] According to them, evolution is a process where more and more ordered forms of life processes are generated, in direct contradiction to the Second Law which states that things tend to move from an ordered to a more disordered state.

The diligent reader will easily see the fallacy of this argument. True, organic evolution does imply a decrease in entropy. But the biosphere is NOT a closed system. There is a constant input of energy from the sun that had energized the chemical and biochemical processes on earth for billions of years allowing order to form. Now, if we take the sun and the earth’s biosphere together, we would get a closed system. And the increase in entropy caused by the thermonuclear processes in the sun outweighs the decrease in entropy resulting from evolution. Thus the second law is not violated by evolution.

The creationists have a standard answer to this explanation. I will quote here from the creationist R.L. Wysong’s book The Creation Evolution Controversy (1976):
 If the decreased entropy and high orderliness of life is accounted for solely on the basis of open system thermodynamics, you might ask why other open systems don’t likewise experience such ordering? [sic] In other words, why don’t battered Volkwagons [sic] in junkyards order themselves into shiny new Cadillacs? A junkyard is an open system. [4]

This objection is really not a valid objection at all, for it misunderstood completely that the discussion on systems and energy transfer must be dependent on the physico-chemical systems involved. In their own way, the creationists are actually asking why the air-conditioner doesn’t work when it is fed with a burger as an energy source and why a human being works even worse when it is fed with energy in the form of an electric current! Air-conditioners require energy in the form of electricity, human beings require energy in from of food which ultimately derives from the sun. Organic forms, the ones that evolve, having similar physicochemical makeup to human being, requires the same kind of energy a people do. Thus we find that the first form of the entropy argument represents a misunderstanding of the applicability of the Second Law of Thermodynamics. As an argument against evolution (and for God’s existence) it is of no worth.

## The Intelligent Design Argument

The second form of the argument involves the whole universe. If the universe consist of everything and all the energy there is, then it must be considered a close system. If this is the case, then the universe must have a constantly increasing entropy. Like an old mechanical clock, it is slowly winding down. Extrapolating backwards, there must be a time when the universe had the lowest possible entropy. The question then is: who wound up the universe? The answer, the theist says, is God. Thus God is defined in the second form of the entropy argument as the “Great Winder Upper”. [5]

This argument while is more sophisticated than the first form is also, ultimately, unconvincing. Here we are at the cutting edge of modern cosmology. Physicists are still trying to figure out what actually happened at the origin of the universe. The answer may be near, but at the moment we still do not know. This represent an actual gap in human knowledge. It is no accident that the modern theist postulate his god as the one who “wound up” the universe. This had always been a well known modus operandi of the theist: namely, whenever you find a gap in human knowledge, that’s where you hide your god! Thus, when our knowledge of life’s origins was lacking, the theistic postulate their god as the creator of life. That gap has been filled by the discovery of the process of organic evolution: the true explanation for the multifarious life forms on earth. When it was not known what caused the sun to shine; the theist say it is kept in such a state by God. The discovery of quantum mechanics in the twentieth century has shown that stars, our sun included, burn due to nuclear fusion in their cores. One more gap has been closed. As George H. Smith observed:

 [T]he theist posits a “god of the gaps”, a god who allegedly fills in the gap of human knowledge. But gaps of knowledge eventually close, leaving god without a home. [6]

However, there are by no means any lack of suggestions and hypotheses as to the actual origin of the universe; none of which need the assumption of the existence of a great “entropy reducer”. One such hypothesis is that suggested by the Cambridge physicist, Stephen Hawking. He combined the General Theory of Relativity with Quantum Mechanics to suggest what is basically an oscillating kind of universe, where upon reaching its maximum limit of expansion, the universe begins to contract. This contraction would cause entropy to actually decrease. Thus when the universe is completely collapsed -the “Big Crunch” - entropy is once again at its lowest point. [7] The universe then re-expands into the next cycle. In this model there is no beginning and no end, just an endless and infinite cycles of oscillations between the Big Bang and the Big Crunch. Thus, even here the gaps for the theist’s god is closing fast.

In summary, the second form of the entropy argument is simply a postulation of an unknown entity that could somehow put the universe in a low entropy state. This is completely unfounded by any evidence and definitely not the only hypothesis available for the entropy problem.

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### Notes

 a. This part of the reasoning is also fallacious. For evolution and creation are not the only two exclusive explanations for the origin of species and life. Proving evolution false does not automatically imply that creationism is true.

### References

 1 Kitcher, Abusing Science: p90 2 Pagels, Perfect Symmetry: p58 3 Kitcher, Abusing Science: p90 4 Quoted in ibid: p94 5 Smith, Atheism: p256 6 Gribbin, In Search of the Big Bang: p391 7 ibid: p386

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