A Closer Look at the Laws of Thermodynamics.
A number of related questions have come in lately about abiogenesis/the origin of life, so we thought it would be a good idea to reproduce an appendix from the book Is There a God (www.ipibooks.com) which addresses this topic. See below.
John Oakes
A Closer Look at the Laws of Thermodynamics
In chapter four the application of the laws of thermodynamics to the question of the origin of life was introduced. The arguments in that chapter can stand on their own. However for those with some scientific background legitimate questions can and have come up which deserve a more thorough treatment. The author has been asked the questions raised in the the following section many times, both in personal conversation and in Q &A sessions at public presentations. The discussion below tends more toward the abstract and the mathematical, which is why it was left for an appendix. Readers with a strong background in chemistry and physics have probably already anticipated some of the arguments to follow. It is hoped that further discussion will also be helpful for those with less science background who are willing to wade through some admittedly tougher material.
Could life have been created by a “natural process”? Can the materialist assumption be upheld in view of what we know about living things and about the nature of entropy? We have already used qualitative arguments to say no. Let us now be more quantitative. The first law of thermodynamics, simply stated, is as follows: “In any process, the total energy of the universe is conserved.” In other words, for any natural process, energy may change forms or move from one place to another, but the total energy content in the universe is constant. No single scientist is given credit for discovering this law. Recognition is shared by French mathematician Sadi Carnot, the brewer and physicist James Prescott Joule and others. In the 1820s Carnot studied the theoretical efficiency limit for heat engines. Joule’s experiments in the 1840s on the mechanical and electrical equivalency of heat are so important that the metric unit of energy is named after him. By the middle of the nineteenth century, this first empirical law of thermodynamics was thought to be more or less proven by the scientific community.
The first law of thermodynamics can be applied to energy conversions such as in the combustion of gasoline. When gas is burned, chemical energy in the molecules is converted to heat and light. The amount of heat and light energy produced will exactly equal the amount of chemical energy used up, assuming no other forms of energy are involved. If the heat produced is harnessed in an internal combustion engine, the chemical energy is turned into heat (lost out the muffler and the radiator as well as due to friction with the road and the air), into mechanical energy to move the car, and into electrical energy to run the lights, the stereo and so forth. In any case, the total amount of energy produced will exactly equal the total energy used up. This law has been extensively confirmed by experiment.
Another conservation law was discovered about forty years before the conservation of energy. The law of conservation of mass was established through some very elegant experiments done by the chemist Antoine Lavoisier in the late 18th century. It can be stated as follows: “In any natural process, the total mass of the universe is conserved.” In other words, in any process which can occur matter is neither created nor destroyed.
In the year 1905, Albert Einstein threw a wrench into this neat set of conservation laws with his theory of special relativity. In a paper published that year he proposed that matter can be converted into energy and energy into matter. This fact is expressed in the famous equation E = mc2. This law states that the amount of energy created (or used up) in a process is equal to the amount of mass used up (or created) in the process times the square of the speed of light. The conversion of matter into energy is demonstrated in nuclear fusion or fission, in which atoms are built up or split apart releasing huge amounts of energy. In normal chemical reactions, the amount of energy involved (E) is so small the amount of mass change (m) is too small to be measured by any standard mass-measuring device, which explains why the law of conservation of mass was accepted for so long. A combined law may be expressed in a more general first law of thermodynamics as follows: “In any process, the total of mass and energy in the universe are conserved.”
The first law of thermodynamics amounts to a mathematics of natural processes. It does not predict whether a particular process can happen; only the result in terms of energy if it does. For this reason, the first law is not the crucial one to help us decide whether life was created or if it began by natural processes. To illustrate this, let us apply the first law to a rock balanced on the edge of a cliff. If it were to leave the edge of the cliff, it is easy to predict what would happen—it would fall! Knowledge of the laws of thermodynamics is not needed to predict this. However, one can apply the first Law to this event by describing what happens in terms of energy. When the rock falls, gravitational potential energy is turned into kinetic energy as the rock accelerates. Some of the energy is lost as heat due to friction with the air. What happens to the kinetic energy when the rock hits the ground? The answer is that it is turned into heat (as well as a little bit of sound energy). If a person quickly went and felt the ground where the rock hit, it would have gotten just a little bit warmer.
This is where the limitations of the first law of thermodynamics become clear. There is nothing in the first law which precludes all the heat energy in the ground coming together and spontaneously causing the rock to be thrown off the ground, up into the air, and back up onto the cliff. One knows intuitively that this process is impossible, but the first law of thermodynamics cannot explain why. If a film was seen showing a large rock suddenly rising off the ground into the air and landing in a delicately balanced position on top of a cliff, the viewer would know instinctively that the film was being run backward. Some processes in nature are only spontaneous in one direction and not in the reverse direction. Well, not quite. If a person used intelligence and planning, he could pick up the boulder and carry it up to the top of the cliff, replacing it in its original position. This apparent exception to the law of spontaneity will be revisited later.
The case above reveals the fact that in nature certain events simply do not happen spontaneously. Remember the example used in chapter four of an old building being demolished, producing a cloud of dust and a large pile of rubble. It is obvious that the pile of rubble and cloud of dust could never spontaneously join themselves together to reform a building with all the pipes soldered together and all the bricks laid straight, cemented in position, etc. This would be absolutely impossible. Don’t forget, though, that buildings do exist. They require an intelligent creator, willing to plan carefully and work hard in order to bring the different components into a carefully ordered state.
The principle by which scientists predict whether processes can occur spontaneously or not is the second law of thermodynamics. Nothing in the first law precludes the possibility of the blown up building being recreated spontaneously out of its dust and rubble. However, the second law of thermodynamics can be used to predict that this process is not possible.
The second law of thermodynamics is more abstract than the first. It is difficult to state it in a way easily understood by the uninitiated. One of the earliest statements of the second law is as follows. “Heat flows spontaneously from hot to cold objects, but not from cold objects to hot objects.” In other words, if you put a hot rock into cold water, the rock would cool off, while the water would get hotter. It is impossible for the hot rock to absorb heat out of the cooler water, causing the cold water to get even colder. It is tempting to say in response, “I did not need some scientist to tell me that.” This is true. However, using this law in the form of an equation, the French physicist Sadi Carnot was able to predict that it is impossible to create a perpetual motion machine—one whose sole function is to convert heat into mechanical energy with 100% efficiency. The work of Carnot and others to improve the efficiency of steam engines by applying the laws of thermodynamics to the problem contributed greatly to the industrial revolution in the nineteenth century.
A later formulation of the second law is that of Clausius. This statement is of relevance to chemistry, and therefore to the question of the origins of life. It can be stated as follows: for any spontaneous process, the entropy of the universe increases. Loosely stated, entropy is a measure of randomness or freedom of motion. In quantitative terms, the entropy of a process is the heat of that process, done in a reversible way, divided by the absolute temperature of the process. If the temperature is not constant while a process occurs, calculus must be used to define entropy.
In any case, Clausius gave us a more general rule to predict whether a process will occur spontaneously. A process which creates more order (less entropy) in the universe will not be spontaneous. To illustrate, let us list a few processes which increase entropy. In doing so, we will see that the concept of entropy is more intuitive than one might expect. For example, when ice is melted, the molecules of water change from a state in which they are fixed in position to one in which they move about freely with random motion. This increased freedom of motion implies that the entropy of liquid water is greater than that of ice. Similarly, when water is boiled, entropy is increased because the water molecules are no longer attracted to one another in steam as they were in water, allowing for more freedom of motion.
Clearly, blowing up a building dramatically increases entropy. On the other hand, the creation of a large building with so much “order,” with all the bricks lined up just right and all the wires attached at the right places requires a very large decrease in entropy. It therefore will not happen spontaneously. (Do not forget, though, that with sufficient external input of energy by an intelligent creator, buildings can be built. More on this later.)
What about chemistry? Large molecules such as DNA, proteins, complex lipids and sugars are in a very low state of entropy. Creating these macromolecules from smaller ones (a necessary process in order for life to be created spontaneously) involves a large decrease of entropy. The great decrease in entropy is due to two factors. First, such molecules reduce the freedom of motion of hundreds or even thousands of atoms by bonding them together. Second, entropy is decreased because of the great degree of order in the three-dimensional structure of the molecules. In order for an enzyme molecule to function, entropy must be reduced in a few ways. First, several atoms must be bound together in just the right way to form the separate amino acids. Second, dozens or hundreds of amino acid molecules need to come together spontaneously. The correct number of each of the twenty naturally occurring amino acids have to be joined in exactly the right order for the enzyme to work. In addition, the three-dimensional shape of the chain of amino acids must be in a very specific arrangement for the enzyme to function. If the primordial soup from which life is supposed to have been created contained any besides the twenty correct amino acids (and it unquestionably would have), they would have to be excluded from the structure. This too requires a decrease in entropy.
Even if by chance a large, complex, ordered thing such as a DNA molecule or an enzyme were somehow to come to exist in apparent violation of the second law of thermodynamics, the same law could be used to predict that the molecule, if subject to the vagaries of the environment, would soon fall apart. It would decompose to smaller, more random chunks of molecule, with more entropy. This is why, as mentioned earlier, Nobel prize-winning chemist Melvin Calvin said that when looking at ancient sediments under bogs, they do not even look for proteins or polysaccharides (sugars), because it is a matter of common knowledge that these molecules are not stable. Why materialists theorize that these molecules slowly built up and evolved into more and more complex structures over great periods of time in some ancient earth environment seems to be beyond explanation. It is also beyond the second law of thermodynamics.
It is tempting to say, “case closed” on the spontaneous origin of viable protein molecules, given that such molecules have very low entropy. However, it is not quite that simple. Processes which decrease entropy do in some cases occur. When water is frozen entropy decreases. Apparently, under the right conditions, ice can be created out of water, even though this results in a decrease in entropy and an increase in order. This raises more questions. Under what conditions can entropy decrease locally? Do the conditions which allow ice to form make it possible for large biomolecules to be produced spontaneously? More importantly, living things clearly do exist and they certainly have very low entropy. Aren’t they violations of the second law of thermodynamics? In order to approach these questions, a more detailed investigation of the second law of thermodynamics is required.
The ice-from-water example will provide a good illustration. It turns out that the statement of the second law of thermodynamics given above, although correct, needs to be put more carefully to be useful. This is true, because entropy can decrease in one place, as long as it increases somewhere else at the same time but by an even greater amount. As noted when water freezes the entropy of the water decreases. However, if the temperature is low enough, when the heat leaves the water to go into the environment (such as in your freezer), it increases the entropy of the environment even more than it decreases the entropy of the water. When objects absorb heat, their entropy increases. Let us use number to illustrate the point. Consider a situation in which as some water freezes, the change of entropy in the water is ΔS = -10 entropy units. (S is the conventional symbol for entropy) If the environment increases in entropy because of the heat it absorbs from the water by ΔS = +15 entropy units, then the total entropy change for the process is ΔS = -10 + 15 = +5 entropy units. In this case the total change of entropy of the universe is positive, and the water will freeze spontaneously.
The fact is that below zero degrees centigrade (32 degrees Fahrenheit), the total entropy change for water to turn to ice is positive, and water freezes spontaneously. Above zero degrees centigrade the total entropy change for water to freeze becomes negative and water will not freeze. Therefore a scientist can calculate the freezing point of water to be zero degrees centigrade, based on the second law of thermodynamics.
Evidently, the simple fact that a process has a negative entropy change is not a sufficient predictor of whether or not it will be spontaneous. In order to make this concept useful for one trying to predict whether a process will be spontaneous, let us describe four possible scenarios, as listed in the table below.
Scenario ΔS system ΔS surroundings Spontaneous?
1 positive positive yes, always
2 positive negative yes, only at high temperature
3 negative positive yes, only at low temperature
4 negative negative never
A process which fits into the first scenario will definitely have a total entropy change which is positive, so it will definitely be spontaneous. A process described by the fourth scenario will definitely have a negative total entropy change and it will therefore definitely not occur spontaneously. Whether a process described by case 2 or 3 is spontaneous depends on the temperature. Water freezing to form ice falls under scenario 3, so it can occur, but only at sufficiently low temperatures. An example of scenario 1 would be paper burning to form carbon dioxide and water. This is a spontaneous process. A process which fits scenario 4 is to chemically combine carbon dioxide and water to form paper. This process requires absorption of heat from the environment, making the entropy change of the environment negative. It also requires the formation of very complex cellulose molecules, making the entropy change of the system negative. The conclusion is that paper will not form spontaneously under any circumstances no matter how much heat one puts into a mixture of the proper gases. No matter how long one waits, it will never happen!
The same criterion can be applied to the supposed pathways by which Carl Sagan, Melvin Calvin and others claim life came into existence by a spontaneous process. The chemical reactions by which the basic molecules of life (carbohydrates, lipids, proteins and nucleic acids) are created from simpler building blocks all absorb heat from the environment; therefore they have a negative entropy change in the environment. They all result in a decrease in entropy in the molecules as well. This falls under scenario 4 described above. Because the formation of biomolecules both absorbs heat and decreases entropy, one can conclude that molecules such as enzymes will never be produced in usable quantity spontaneously out of a soup of simple molecules even if one waits indefinitely. This argument applies to the spontaneous production of a usable quantity of just one functioning enzyme molecule. It is a great leap from this point to even begin to propose the production (simultaneously and at the same place) of thousands of different molecules of carbohydrates, proteins and nucleic acids—all self-assembling inside a lipid bilayer to form a unit which is able to ingest food, grow, and reproduce.
But there is still one more question to be answered. This is probably the hardest one to deal with of all. Clearly paper exists, and it has rather low entropy. Despite the second law of thermodynamics, it is undeniable that living things exist . Even if God created living things, does not the very continued existence of living things constitute a violation of the second law of thermodynamics? Don’t living things have to make proteins, nucleic acids and so forth, with very low entropy, in apparent violation of the second law? It is time to answer this intriguing question.
How can life exist with its extreme amount of order—with its unaccountably low entropy? The answer is that all living things have an energy-fixing mechanism. In other words, all living things have the ability to derive usable energy from their environment, and to use that energy to decrease entropy (for example to synthesize large, ordered molecules). A living thing has an extremely complex set of metabolic pathways; a series of chemical steps controlled by enzyme molecules which it uses to turn food into the raw materials (sugars, fats or amino acids) for metabolism, eventually converting the energy in food into such energy-storing molecules as ATP (adenosine triphosphate). The energy stored in these molecules, used in an intelligent way, allows the living cell to synthesize large protein and nucleic acid molecules—those molecules which allow a living thing to eat, grow, reproduce and think, etc.
The bottom line is that if energy is used in a carefully controlled way, it can be used to reduce entropy locally at the expense of increasing entropy globally. This is demonstrated in a refrigerator. A refrigerator moves heat from a cold place to a hot place. At first glance this would be in direct violation of the original statement of the second law. However, the second law allows for the possibility of energy from outside a system being used to decrease entropy locally, if it is incorporated into a system in a carefully controlled way. The point to be made here is that refrigerators do not create themselves. It takes a thinking, planning designer to create a device such as a refrigerator. The same is true, except to an inconceivably greater degree, in the design of a living thing.
Remember the boulder which fell off the cliff in an earlier illustration? It is possible for a being with a purpose in mind to take the boulder, carry it up the hill, and place it balanced precariously at the edge of the cliff. Of course, such a process would involve the one carrying the boulder back up the hill to increase the entropy of his or her environment at the same time. This simple example illustrates the problem nicely. Imagine trying to pump a lot of energy into the boulder at the bottom of the cliff in some sort of random fashion. Perhaps by some amazing accident, the energy could conceivably cause the rock to be thrown up into the air, landing at the edge of the cliff, but it is incalculably more likely to destroy the rock. Energy incorporated into a system with out intelligent flow of that energy is very limited in what it can accomplish.
One of my favorite subjects to teach is biochemistry. In studying this subject one gets a glance at the overwhelming chemical complexity of even the simplest living system. This sort of thing, with its great order (and very low entropy), is made possible because a very intelligent designer created a chemical system which can incorporate food energy in such a way which allows the system to synthesize the very chemicals which allowed it to incorporate the food in the first place. Which came first, the chicken or the egg?
This brings the argument to the last stand of the materialists as they attempt to save the religion of scientism which excludes the possibility of a transcendent creator. They claim that if sufficient energy were available (from sunlight, or perhaps from thermal vents in the ocean), given the right building blocks, and sufficient time, entropy could be reduced enough in some local environment to spontaneously produce a living thing. Given our
description of how a refrigerator works, this almost sounds plausible.
What Marina The Marina District in San Francisco after the Loma Prieta earthquake…..?
However, this scenario is not possible. This is because if sufficient energy is input into a system in a non-intelligent way, thermal entropy may be reduced, but informational entropy cannot.
The creation of life by spontaneous chemical event requires a reduction in both kinds of entropy. When thermal entropy is reduced, ordered arrangements are created from disorder, such as disordered liquid water molecules acquiring a definite geometric pattern when they are turned into ice. However, ice does not contain information. Reducing thermal entropy can produce a repeating pattern, but it cannot produce non-random information. When gasoline is burned in an internal combustion engine, the energy produced can be used to compress a gas, move a piston, and cause a car to go uphill. In this case energy is used to cause a normally non-spontaneous process (a car moving uphill) to happen, but it is not producing information.
None of these illustrations involve a decrease in informational entropy. Consider a room with a pack of playing cards randomly distributed on the floor. Now, picture a backward vacuum cleaner pointed at the cards as a source of energy. It could be used to push all the cards into the corner, decreasing the “thermal entropy.” However, it could not be used to place the cards into four separate piles of hearts, clubs, diamonds and spades. It could also not be used to build a house out of cards. The likelihood of the backward vacuum cleaner creating a house of cards is zero. Energy can only be used to build a house of cards or to create neat stacks of cards sorted by suit if the energy is directed by design. Simply throwing energy at a system will never decrease the informational entropy of that system to a significant degree. The fact is that thermal energy always tends to decrease information.
The refrigerator provides another case in point. A refrigerator can be used to reduce entropy inside the device. It uses up electrical energy to reduce thermal entropy. However throwing a lot of energy at the raw materials needed to produce a refrigerator could never result in the production of a refrigerator. There is no way that one could take a pile of iron ore and crude petroleum as well as all the other raw materials required to build a refrigerator, and then simply add energy and wait long enough for a refrigerator to result, with the bolts turned into the proper holes, the belt on the motor and so forth. A design is required to direct the flow of energy needed to create the refrigerator. Why? Because the refrigerator contains information.
There is no way around this fact of nature. Nature does not create information by itself. Materialists, intent on preserving belief in the random creation of life, simply avoid the unavoidable requirement for a great decrease in informational entropy in order for life to be created by ignoring it. One exception to this rule is Belgian chemist Ilya Prigogine, who received the Nobel prize for his work on non-equilibrium thermodynamics. He discussed the distinction between reducing thermal and informational entropy as it relates to the origin of life.
Needless to say, these simple remarks cannot suffice to solve the problem of prebiological order. One would like not only to establish that the Second Law (S>0) is compatible with a decrease in the overall (system) entropy (S<0), but also to indicate the mechanisms responsible for the emergence and maintenance of coherent states.
Prigogine and his co-author Nicolis point out that it is not enough to show that overall system entropy (what I am calling thermal entropy) can be reduced by inputting energy. The question to be asked is how did “prebiological order” or “coherent states” come to be? Scientists have no answer to this question, or they refer to “chemical evolution” and “sufficient time” as the explanation. This amounts to hand-waving. Use of these nice-sounding terms does nothing to change the fact that more and more energy and more and more time will always yield an increase in informational entropy, not a decrease. Information simply does not gradually increase in nature without an intelligent injection of energy.
Humans are quite good at creating objects with low informational entropy. Such objects illustrate the general rule that intelligence or design is required for energy to be used to create information. Consider a blank cassette tape. It contains magnetic material which, when the tape is bought, is randomly oriented (high entropy). When an electric signal proportional to the sound of a musical instrument is run through the record head, the magnetic field on the tape is unrandomized (low informational entropy), producing sufficient order that it is able to cause music to be played back when the magnetic signal is read. Does anyone believe that the applying magnetic energy to a tape at random could ever produce a piece of music, with a rhythm, lyrics and so forth? The answer is an emphatic “No!” This would require a large reduction in informational entropy. It could only be done by intelligent design.
Even the simplest living organism is much more complex and has much more information than a house of cards or even the cassette tape of a musical piece. In other words, the probability of a backward vacuum cleaner being applied to a pile of playing cards producing a well-designed house of cards is far greater than the chances of a prebiological soup producing even one usable gene, never mind all the thousands of proteins, carbohydrates, nucleic acids and lipids needed to produce a living thing.
In fact, the probability of a house of cards being built by a backward vacuum cleaner is not just small; it is zero. Even if by some amazing coincidence all the cards just happened to be in the right position to form a house at some instant in time, the very vacuum which created the house in the first place would instantaneously destroy it. This is another reason the proposal of scientists that an unlimited amount of energy could create a large degree of informational order is illogical. The large amount of energy required to decrease the entropy in a chemical system (or a group of cards) would very quickly randomize that information, even if it were instantaneously produced.
There is the rub. The magic ingredient which believers in non-transcendent creation of life always invoke is time. The problem with this is that with systems which are not controlled intelligently, time inevitably produces higher entropy, not lower. Very unlikely events will have their probability increased by waiting. If one plays the lottery ten million times, the probability of winning goes up. However, impossible events, such as those that grossly decrease informational entropy without the intervention of an intelligence, will not become more possible with time. To illustrate, the probability of a very large asteroid hitting the earth this year is extremely low. However, it can be predicted that in the time span of a billion years, this very small probability will increase to the point that the event actually becomes likely over that very great time span. Picture the reverse process, the impossible one. Imagine running an asteroid collision backwards. In other words, imagine trillions of dust particles, small rocks, many huge boulders as well as millions of gas particles spontaneously joining themselves together to become a giant asteroid, which then lifts itself off the surface of the earth to be hurtled back into space. This is an impossible event, whose probability will not grow with time. The same concept applies to the formation of life without a creator.
This brings us back to our last problem. In view of the need to reduce informational entropy, how does life maintain itself? Living cells are able to break the law of information production because they already contain information. The information essential to life is contained in its DNA. This information is able, intelligently, to direct the synthesis of proteins, carbohydrates, lipids and, most significantly, the reproduction of the information for the next generation of cells. Without the pre-existent information in a cell, such processes are impossible. Living cells also have the amazing property of being able to produce exact copies of their information. This extremely complicated process, governed by many enzymes, is called DNA replication.
How much information are we taking about? Let us take as our model the same e. coli bacteria mentioned previously. The genome of bacteria is considerably smaller than that of humans, involving millions of base pairs as opposed to some four billion. The genome of e. coli is 4.6 million base pairs. For the sake of argument, let us allow that the simplest primitive life could contain as few as two million base pairs in its DNA. This is equivalent to a book of about one thousand pages. Is it possible for two million letters, commas, periods and spaces, thrown randomly at a piece of paper, to produce a book that makes sense? This is literally impossible. Time, energy and a limitless supply of letters will not produce a one thousand book which makes sense. But even the illustration of letters placed at random on a page is far too simple, as a living thing has levels of order and information above and beyond the simple two million pieces of information contained in the nucleic acids. Remember, the first living thing had to simultaneously contain both the DNA with its two million pieces of information and the proteins which, conceptually, would have been formed by that DNA. The proteins in this accidental cell need to be the correct ones so that the DNA which forms them can in turn be formed by the proteins. Add to that the information contained in the lipids, carbohydrates and so forth, and one begins to see the enormity of the problem. Besides, the world in which life is supposed to have formed was far less amenable to the accumulation of information than our model of a piece of paper at which we throw letters.
A great number of additional problems with the formation of life by random natural process could be mentioned. Hopefully the point has been made. It is tempting to quote statistics and probabilities, such as the probability of making a particular chain of protein out of a random sample of amino acids, or the probability of excluding other extraneous molecules at the same time and so forth. Throwing out extremely small numbers and multiplying them to produce even smaller numbers could go on ad infinitum. In the end, the informational requirement reduces the probability of even a single usable molecule of DNA being produced to zero. The interested reader will find a good reference which covers both the probability arguments and the informational entropy concept more thoroughly in paper by Walter L. Bradley.
In summary, the laws of thermodynamics imply that life could never have been produced by natural processes. No amount of scientific fast talk will change this fact. The reason many scientists cling to the natural explanation for the origin of life is either a lack of sufficient understanding of the relevant scientific laws or, more likely, an unwillingness to give up the preconception that natural laws alone explain everything that ever has happened or ever will happen. Great amounts of information can only be created by a system which already contains information. Intelligent input of energy is required to reduce informational entropy. Life requires an intelligent creator.