DNA, Design,
and the Origin of Life

Charles B. Thaxton, Ph.D.

 


This paper was presented as part of the conference, Jesus Christ: God and Man, an international conference in Dallas, Texas, November 13-16, 1986. Dr. Thaxton was then Director of Research, The Julian Center, P.O. Box 400, Julian, CA 92036.

© 1986 by Charles B. Thaxton


The classical design argument looked at order in the world and concluded that God must have caused it. Archdeacon William Paley{1} in the nineteenth century refined the argument. He also gave it perhaps its most eloquent and persuasive formulation. Paley looked at the order of human artifacts and compared it to the order in living beings. If human intelligence was responsible for artifacts, reasoned Paley, then some intelligent power greater than man must have accounted for living beings.

The major problem with this design argument was its claim to reason from order in the world to a supernatural designer. For Paley did not provide any uniform experience of the supernatural, which alone could make good his claim. As valid as this objection was, however, only philosophers seemed concerned about it. It was an argument by Charles Darwin that raised doubt for most people concerning true design in the world.{2} According to Darwin natural selection produced apparent design which the faithful mistook for true design. So the matter has stood in the scientific community and the world at large for a century.

Scientific discoveries made in this century, however, threaten to change the outlook fundamentally in regards to design. However, few outside the relevant disciplines seem aware of it. I am referring to developments in relativity theory and quantum mechanics,{3} neurophysiology,{4} information theory,{5} and molecular biology, particularly the elucidation of the structure of DNA (deoxyribonucleic acid).{6} I shall focus my remarks on DNA and its relation to design and the origin of life. 

Due to advances in molecular biology, the process of reproduction, or self-replication, has become better understood. At the core of this process is the DNA molecule. Though not itself alive, DNA is usually regarded as the sine qua non of life. DNA is considered the identifying mark of a living system. We judge something as living if it contains DNA.

Molecular biology has shown us how extremely intricate living things are, especially the genetic code and the genetic process. Interestingly enough, the genetic code can be best understood as an analogue to human language. It functions exactly like a code -- indeed, it is a code: it is a molecular communication system within the cell.

A sequence of chemical 'letters' stores and transmits the communication in the cell. Communication is possible whatever symbols used as an alphabet. The 26 letters we use in English, the 32 Cyrillic letters used in the Russian language, or the 4-letter genetic alphabet -- all serve in communication.

In recent years, scientists have applied information theory to biology, and in particular to the genetic code. Information theory is the science of message transmission developed by Claude Shannon and other engineers at Bell Telephone Laboratories in the late 1940s. It provides a mathematical means of measuring information. Information theory applies to any symbol system, regardless of the elements of that system. The so-called Shannon information laws apply equally well to human language, Morse code, and the genetic code.

The conclusion drawn from the application of information theory to biology is there exists a structural identity between the DNA code and a written language. H.P. Yockey notes in the Journal of Theoretical Biology:

It is important to understand that we are not reasoning by analogy. The sequence hypothesis [that the exact order of symbols records the information] applies directly to the protein and the genetic text as well as to written language and therefore the treatment is mathematically identical.{7}

This development is highly significant for the modern origin of life discussion. Molecular biology has now uncovered an analogy between DNA and written human languages. It is more than an analogy, in fact: in terms of structure, the two are "mathematically identical." In the case of written messages, we have uniform experience that they have an intelligent cause. What is uniform experience? It simply means that people everywhere observe a certain type of event always in association with a certain type of cause. When we find evidence that a similar event happened in the past, it is reasonable to infer it had a similar cause. As I shall argue, based on uniform experience there is good reason to accept an intelligent cause for the origin of life as well.{8},{9}

 Two Kinds of Order

You may recognize this argument for an intelligent cause of life. It is a form of the design argument that has been popular among theists for centuries. The design argument makes use of the same mode of reasoning used in the historical sciences today -- namely, the argument from analogy. The design argument assumes that the order we see in the world around us bears an analogy to the kind of order exhibited by human artifacts, by tools and machines and works of art. Since the two kinds of order are similar, the cause of one must be similar to the cause of the other. The order in human artifacts is the result of human intelligence. Therefore, the order in the world must be the result of an intelligent being we call the creator.

The argument from molecular biology is a modern restatement of the argument from design, with a few significant refinements. The older design argument went straight from order in the universe to the existence of God. From time immemorial, the beauty of birds and flowers, the cycle of the seasons, the remarkable adaptations in animals, have led people to posit some type of intelligent cause behind it all. Not just Christians but a wide range of believers in some form of intelligence have buttressed their belief by appealing to the wonderful order and complexity in the world.{10}

During the Scientific Revolution of the seventeenth century, the argument from order took on even greater force. Scientists studied the intricate structures in nature in a depth and detail unknown in previous ages. Many became more convinced than ever that such order required an intelligent cause. Isaac Newton expressed a common sentiment when he declared, "this most beautiful system of the sun, planets, and comets, could only proceed from the counsel and dominion of an intelligent and powerful Being."{11} The argument from design has always been the argument most widely accepted by scientists. It is the most empirical of the arguments for God, based as it is on observational premises about the kind of order we discover in nature.{12} Ironically, it was also the Scientific Revolution which eventually led many to reject the argument from design. Repeatedly, scientists discovered natural causes for events which until then had been mysterious. If natural causes could explain these things, perhaps they could explain everything else too. Do we really need an intelligent cause to explain the order of the world?

Take, for example, the structure of a snowflake. The intricate beauty of a snowflake has led many a believer to exclaim upon the wisdom of the creator. Yetthe snowflake's structure is nothing mysterious or supernatural. It is explained by the natural laws that govern the crystallization of water as it freezes.

The argument from design claims that the order we see around us cannot have arisen by natural causes. The snowflake seems to refute that claim. It demonstrates that at least some kinds of order can arise by natural causes. And if matter alone can give rise to order in some instances, why not in all others as well? Why do we need to appeal to an intelligent being any more to explain the origin of the world? We need only continue to search for natural causes. Many materialists today use this argument.{13}

What is coming to light through the application of information theory is there are actually two kinds of order. The first kind (the snowflake's) arises from constraints within the material the thing is made of (the water molecules). We cannot infer an intelligent cause from it, except possibly in the remote sense of something behind the natural cause. The second kind, however, is not a result of anything within matter itself. It is in principle opposed to anything we see forming naturally. This kind of order does provide evidence for an intelligent cause.

The Difference It Makes

Let's explain these two kinds of order in greater detail. As you travel through various parts of the United States, you may come across unusual rock formations. If you consult a tourists' guide, you will learn that such shapes result when more than one type of rock make up the formation. Because their mineral composition varies, some rocks are softer than others. Rain and wind erode the soft parts of the formation faster than the hard parts, leaving the harder sections protruding. In this way, the formation may take on an unlikely shape. It may even come to resemble a familiar object like a face.

In other words, the formation may look as though it was deliberately carved. However, on closer inspection, say from a different angle, you notice the resemblance is only superficial. The shape invariably accords with what erosion can do, acting on the natural qualities of the rock (soft parts worn away, hard parts protruding). You therefore conclude the rock formed naturally. Natural forces suffice to account for the shape you see.

Now let's illustrate a different kind of order. Say in your travels you visit Mount Rushmore. Here you find four faces on a granite cliff. These faces do not follow the natural composition of the rock: the chip marks{14} cut across both hard and soft sections. These shapes do not resemble anything you have seen resulting from erosion. In this case the shape of the rock is not the result of natural processes. Rather, you infer from uniform experience that an artisan has been at work. The four faces were intelligently imposed onto the material.

None of us finds it difficult to distinguish between these two kinds of order, the one produced naturally and the other by intelligence. To come back to the argument from design, the question is: which kind of order do we find in nature?

If we find only the first kind, then our conclusion will be that natural causes suffice to explain the universe as we see it today. An intelligent cause, if there is one, is merely a distant First Cause. It is a deistic kind of God who created matter with certain tendencies and then stood back to let these work themselves out mechanically.

If, on the other hand, we find any instances of the second kind of order, the kind produced by intelligence, these will be evidence of the activity of an intelligent cause. Science itself would then point beyond the physical world to its origin in an intelligent source.

It is easy enough to find examples of the first kind of order. The snowflake was one. The properties of the atoms that compose a snowflake determine its crystalline structure. Wind and temperature explain cloud shapes. Ripples of sand on a beach result from the impact of wind and waves. The waves of the sea form by wind, gravity, and the fluid properties of water. None of these goes beyond what we expect to result naturally, given the properties of the material itself. The beauty of a sunset may inspire poets, but natural causes suffice to explain it.

The most pervasive example of the second kind of order is life itself.

 A Code In Miniature

One of the greatest scientific developments of the twentieth century has been the discovery of the DNA code. DNA is the famous molecule of heredity. Each of us begins as a tiny ball about the size of a period at the end of a sentence. All our physical characteristics, i.e., height, hair color, eye color, etc., are 'spelled out' in our DNA. It guides our development into adulthood.

The DNA code is quite simple in its basic structure (although enormously complex in its functioning). By now most people are familiar with the double helix structure of the DNA molecule. It is like a long ladder, twisted into a spiral. Sugar and phosphate molecules form the sides of the ladder. Four bases make up its 'rungs.' These are adenine, thymine, guanine, and cytosine. These bases act as the 'letters' of a genetic alphabet. They combine in various sequences to form words, sentences, and paragraphs. These base sequences are all the instructions needed to guide the functioning of the cell.

The DNA code is a genetic 'language' that communicates information to the cell. The cell is very complicated, using many DNA instructions to control its every function. The amount of information in the DNA of even the single-celled bacterium, E. coli, is vast indeed. It is greater than the information contained in all the books in any of the world's largest libraries. The DNA molecule is exquisitely complex, and extremely precise: the 'letters' must be in a very exact sequence. If they are out of order, it is like a typing error in a message. The instructions that it gives the cell are garbled. This is what a mutation is.

The discovery of the DNA code gives the argument from design a new twist. Since life is at its core a chemical code, the origin of life is the origin of a code. A code is a very special kind of order. It represents "specified complexity."{15} To understand that term, we need to take a brief excursion into information theory as it applies to biology.

 Measuring Information

"One if by land, two if by sea." Paul Revere did not know information theory, but he was using its principles correctly. A simple but effective code informed the Patriots of the British route of approach.

Information theory realizes an important goal of mathematicians, to make information measurable. It finds its place in biology through its ability to measure organization and to express it in numbers. Biology has long recognized the importance of the concept of organization. However, little practical was possible until there was a way to measure it. Organization stated in terms of information does this. "Roughly speaking," says Leslie Orgel, "the information content of a structure is the minimum number of instructions needed to specify the structure."{16} The more complex a structure is, the more instructions needed to specify it.

Random structures require very few instructions at all. If you want to write out a series of nonsense letters, for example, here is all you do. The only instructions necessary are "write a letter between A and Z," followed by "now do it again," ad infinitum.

A highly ordered structure likewise requires few instructions if its order is the result of a constantly repeating structure. A whole book filled only with the sentence "I love you" repeated over and over is a highly ordered series of letters. A few instructions specify which letters to choose and in what sequence. These instructions followed by "now do it again" as many times as necessary completes the book. By contrast with either random or ordered structures, complex structures require many instructions. If we wanted a computer to write out a poem, for example, we would have to specify each letter. That is, the poem has a high information content.

 Specifying a Sequence

Information in this context means the precise determination, or specification, of a sequence of letters. We said above that a code represents "specified complexity." We are now able to understand what "specified" means. A thing is more highly specified the fewer choices there are about fulfilling each instruction. In a random situation, options are unlimited and each option is equally probable. In generating a list of random letters, for instance, there are no constraints on the choice of letters at each step. The letters are unspecified.

An ordered structure, on the other hand, like our book of "I love you's," is highly specified. Each letter is specified. Nonetheless, it has a low information content, as noted before, because the instructions needed to specify it are few. Ordered structures and random structures are similar in that both have a low information content. However, they differ in that ordered structures are highly specified.

A complex structure like a poem is likewise highly specified. It differs from an ordered structure, however, in that it is not only highly specified, but also has a high information content. Writing a poem requires new instructions to specify each letter.

To sum up, information theory has given us tools to distinguish between the two kinds of order we spoke about at the beginning. Lack of order -- randomness -- is neither specified nor high in information.

The first kind of order is the kind found in a snowflake. Using the terms of information theory, a snowflake is specified but has a low information content. Its order arises from a single structure repeated over and over. It is like the book filled with "I love you." The second kind of order, the kind found in the faces on Mount Rushmore, is both specified and high in information.

 Life Is Information

Molecules characterized by specified complexity make up living things. These molecules are, most notably, DNA and protein. By contrast, nonliving things fall into one of two categories. They are either unspecified and random (like lumps of granite and mixtures of random nucleotides), or they are specified but simple (like snowflakes and crystals). A crystal fails to qualify as living because it lacks complexity. A chain of random nucleotides fails to qualify because it lacks specificity.{17} No nonliving things (except DNA and protein in living things, human artifacts and written language) have specified complexity.

For a long time biologists overlooked the distinction between two kinds of order (simple, periodic order versus specified complexity). Only recently have they appreciated that the distinguishing feature of living systems is not order but specified complexity.{18} The sequence of nucleotides in DNA, or of amino acids in a protein, is not a repetitive order like a crystal. Instead it is like the letters in a written message. A message is not composed of a sequence of letters repeated over and over. It is not, in other words, the first kind of order.

Indeed, the letters that make up a message are in a sense random. There is nothing inherent in the letters "g-i-f-t" that tells us the word means "present." In fact, in German the same sequence of letters means "poison." In French the series is meaningless. If you came across a series of letters written in the Greek alphabet and didn't know Greek, you wouldn't be able to read it. Nor would you be able to tell if the letters formed Greek words or were just groupings of random letters. There is no detectable difference.

What distinguishes a language is that certain random groupings of letters have come to symbolize meanings according to a given symbol convention. Nothing distinguishes the sequence a-n-d from n-a-d or n-d-a for a person who doesn't know any English. Within the English language, however, the sequence a-n-d is very specific, and carries a particular meaning.{19}

There is no detectable difference between the sequence of nucleotides in E. coli DNA and a random sequence of nucleotides.{20} Yet within the E. coli cells, the sequence of "letters" of its DNA is very specific. Only that particular sequence is capable of biological function.

The discovery that life in its essence is information inscribed on DNA has greatly narrowed the question of life's origin. It has become the question of the origin of information. We now know there is no connection at all between the origin of order and the origin of specified complexity. There is no connection between orderly repeating patterns and the specified complexity in protein and DNA. We cannot draw an analogy, as many do, between the formation of a crystal and the origin of life. We cannot argue that since natural forces can account for the crystal, then they can account for the structure of living things. The order we find in crystals and snowflakes is not analogous to the specified complexity we find in living things.{21}

Are we not back to a more sophisticated form of the argument from design? With the insights from information theory we need no longer argue from order in a general sense. Order with low information content (the first kind) does arise by natural processes. However, there is no convincing experimental evidence that order with high information content (the second kind or specified complexity) can arise by natural processes. Indeed, the only evidence we have in the present is that it takes intelligence to produce the second kind of order.

 The Present As the Key to the Past

Scientists can synthesize proteins suitable for life. Research chemists produce things like insulin for medical purposes in great quantities. The question is, how do they do it? Certainly not by simulating chance or natural causes. Only by highly constraining the experiment can chemists produce proteins like those found in living things. Placing constraints on the experiment limits the 'choices' at each step of the way. That is, it adds informataion. If we want to speculate on how the first informational molecules came into being, the most reasonable speculation is there was some form of intelligence around at the time.

The scientists searching for extra-terrestrial intelligence (ETI) would recognize the kind of order inherent in a decodable signal{22} from space as evidence of an intelligent source. These scientists have never seen an extra-terrestrial creature. However, they would recognize the similarity of a message from space to messages generated by human intelligence. In the same way, we note that the structure of protein and of DNA has a high information content. We recognize its similarity to information (like poems and computer programs) generated by human intelligence. Therefore we may properly infer that the source of information on the molecular level was likewise an intelligent being.{23} Furthermore, we know of no other source of information. Efforts to produce information-bearing molecules by chance or natural forces have failed. We have not seen the creator, nor observed the act of creation. However, we recognize the kind of order that only comes from an intelligent being.

With the new data from molecular biology and information theory, we can now argue for an intelligent cause of the origin of life. It is based on the analogy between the DNA code and a written message. We cannot identify that source any further from the scientific data alone. We cannot supply a name for that intelligent cause. We cannot be sure from the empirical data on DNA whether the intelligence is within the cosmos but off the earth as asserted by Hoyle and Wickramasinghe.{24} It might be beyond the cosmos as historic theism maintains. All we can say is that, given the structure of a DNA molecule, it is certainly legitimate to conclude that an intelligent agent made it. Life came from a who rather than a what. We may be able to identify that agent in greater detail by other arguments. We may, for example, gain insight from historical, philosophical, or theological argument, or by considering the relevant lines of evidence from other areas of science. However, from scientific data on DNA alone we can argue only to an intelligent cause.

Let's spell out the steps of the argument more explicitly. Does it in fact satisfy the principle of analogy? Yes, it does. First, we establish that an analogy does exist between the kind of order we see in living things and the kind we see in some other phenomena made by human intelligence.{25} We have an abundance of examples of specified complexity: books, machines, bridges, works of art, computers. All these are human artifacts. In our experience only human language and human artifacts match the specified complexity exhibited by protein and DNA. Second, we ask what is the source of the order in these modern examples? We know by uniform experience that its source is human intelligence.

The only remaining question is whether it is legitimate to use this reasoning to infer the existence of an intelligent cause before the existence of human beings. I would argue it is. A phenomenon from the past, known by uniform experience to be like that caused only by an intelligent source, is itself evidence that such a source existed. Even the simplest forms of life, with their store of DNA, are characterized by specified complexity. Therefore life itself is prima facie evidence that some form of intelligence was in existence at the time of its origin.{26}

It is true that our actual experiential knowledge of intelligence is limited to carbon-based organisms, particularly human beings. However, scientists already speculate on some other kinds of intelligence, i.e., non-human, when they seriously seek to discover ETI's.{27} Some even argue that intelligence exists in complex non-biological computer circuitry. Scientists today conceive of intelligence freed from biology as we know it. Then why can we not conceive of an intelligent being existing before the appearance of biological life on this planet?

 Uniform Experience

In scientific terms, the analogy criterion is the same thing as the principle of uniformity. It is the dictum that our theories of the past must invoke causes similar to those acting in the present. David Hume was getting at the same idea with his phrase, "uniform experience."{28}

As regards the origin of life, our uniform experience is that it takes an intelligent agent to generate information, codes, messages. As a result, it is reasonable to infer there was an intelligent cause of the original DNA code. DNA and written language both exhibit the property of specified complexity. Since we know an intelligent cause produces written language, it is legitimate to posit an intelligent cause as the source of DNA.

We have now defined the DNA code as a message. It is now clear that the claim that DNA arose by material forces is to say that information can arise by material forces. However, the material base of a message is completely independent of the information transmitted. The material base could not have anything to do with the message's origin. The message transcends chemistry and physics.{29}

When I say a message is independent of the medium which conveys it, I mean that the materials used to send a message have no affect whatever on the content of the message. The content of "Apples are sweet" does not change when I write it in crayon instead of ink. It is unaffected by a switch to chalk or pencil. I can say the same thing if I use my finger and write it in the sand. I can also use smoke and write it in the sky. I can translate it into the dots and dashes of Morse code. Even people holding up posters at a baseball game can transmit the same information.

The point is, there is no relationship at all between information and the material base used to transmit it. The ink or chalk I use to write "Apples are sweet" does not itself look red, nor taste sweet like an apple. There is nothing in the ink molecules that compels me to write precisely or only that particular sentence. The information transmitted by my writing is not within the ink I use to write it. Instead, an outside source imposes information upon the ink using the elements of a particular linguistic symbol system.

The information within the genetic code is likewise entirely independent of the chemical makeup of the DNA molecule. The information transmitted by the sequence of bases has nothing to do with the bases themselves. There is nothing in the chemicals themselves that originates the communication transmitted to the cell by the DNA molecule.

These rather obvious facts are devastating to any theory that assumes life first arose by natural forces. Such theories dominate the intellectual landscape today. Some theories assume that self-organizing properties within the chemicals themselves created the information in the first DNA molecule.{30} Others assume external self-organizing forces created DNA.{31},{32} ,{33} Yet this is tantamount to saying the material used to transmit information also produced it. It is as though I were to say it was the chemical properties of the ink itself that caused me to write "Apples are sweet."

We can state our case even more strongly. To accept a material cause for the origin of life actually runs counter to the principle of uniformity. Uniform experience reveals that only an intelligent cause regularly produces specified complexity. To be sure, we may still posit a non-intelligent, material cause as the source of specified complexity, even though we do not regularly observe it. We may argue that in the rare occurrence, in spite of its trivially small probability, such an event might happen. The problem is, however, that to argue this way is no longer to do science. Regular experience not negligible probabilities and remote possibilities is the basis of science.

Darwin convinced many of the leading intellectuals in his time that design in the world is only apparent, that it is the result of natural causes. Now, however, the situation has taken a dramatic turn, though few have recognized its significance. The elucidation of DNA and unravelling the secrets of the genetic code have opened again the possibility of seeing true design in the universe.

Notes and References

{1}William Paley, [1802], 1835. Natural Theology, Boston: Gould, Kendall and Lincoln.

{2}Charles Darwin, The Origin of Species, [1859], 1963. New York: Washington Square Press.

{3}James S. Trefil, 1983. The Moment of Creation. New York: Charles Scribner's Sons.

{4}Sir Karl Popper and Sir John Eccles, 1977. The Self and Its Brain, New York: Springer-Verlag.

{5}Claude E. Shannon and Warren Weaver, 1964. The Mathematical Theory of Communication. Urbana: University of Illinois Press.

{6}J.D. Watson and F.H.C. Crick, 1953. "The Structure of DNA," Cold Spring Harbor Symposium Quantitative Biology 18: 123.

{7}Hubert P. Yockey, 1981. "Self Organization Origin of Life Scenarios and Information Theory," J. Theoret. Biol. 91, 13. Quote on p. 16.

{8}C. Thaxton, W. Bradley, and R. Olsen, 1984. The Mystery of Life's Origin, New York: Philosophical Library. See Epilogue.

{9}C. Thaxton, 1987. Origins and Natural Science, (to be published).

{10}Origins, 1984. The Bhaktivedanta Institute, 3764 Watseka Avenue, Los Angeles, CA 90034. Copies may be purchased from a local Hare Krishna representative or by contacting the Institute directly.

{11}Isaac Newton, [1687], 1952. "General Scholium," Mathematical Principles of Natural Philosophy, Chicago: Great Books of the Western World. R.M. Hutchins, ed., p. 369.

{12}Frederick Ferre, 1973. "Design Argument," Dictionary of the History of Ideas, Vol. I., New York: Charles Scribner's Sons, p. 673.

{13}The person who accepts an intelligent cause might respond that this merely pushes the question back a step. We still have to account for the order built into the water molecules themselves which causes them to crystallize in such delightful patterns. Where did this order come from?

{14}Actually the "chip marks" were not due to conventional chisels of artisans. Small charges of explosive were used to blast away the unwanted granite, merelly adding to the wonder of this National Monument.

{15}The term comes from Leslie Orgel, 1973. The Origins of Life, New York: John Wiley & Sons, p. 189.

{16}Leslie Orgel, 1973. The Origins of Life, New York: John Wiley & Sons, p. 190.

{17}ibid, p. 189.

{18}The mathematical basis for distinguishing order from complexity is given by H. Yockey, 1977. "A Calculation of the Probability of Spontaneous Biogenesis by Information Theory," J. Theoret. Biol. 67, 377.

{19}In Henry Quastler's colorful expression, it is an "accidental choice remembered." The Emergence of Biological Organization, New Haven: Yale University Press, 1964, pp. 15-17.

{20}No different, that is, merely in terms of nucleotide base sequences. There are other differences, however, between the DNA of living things and random mixtures of nucleotides. The greatest difference is that the DNA of living things contains the optically active, right-handed, sugar d-deoxyribose whereas a random mixture contains equal amounts of both d- and l-, or right- and left-handed forms.

{21}H. Yockey, ibid, p. 380.

{22}In the case of ancient Egyptian hieroglyphics scholars could only guess that the markings contained a message until the Rosetta Stone was discovered as a decoding key. Likewise, without such a decoding key a message from space might never be recognized, and thus never understood.

{23}Opposed to this is the "manana argument" -- tomorrow we will find a natural cause. However, since we already have clear, unmistakable evidence for intelligent production of specified complexity, the burden is on opponents to show a natural cause can also produce it.

{24}Fred Hoyle and Chandra Wickramasinghe, 1981. Evolution From Space, New York: Simon and Schuster. Note that Hoyle and Wickramasinghe do not argue for an intelligent cause, but against a natural cause.

{25}David Hume, [1748], 1952. An Enquiry Concerning Human Understanding, Chicago: Great Books of the Western World. R.M. Hutchins, ed., pp. 462, 499. "From causes which appear similar we expect similar effects.... the same rule holds, whether the cause assigned be brute unconscious matter, or a rational intelligent being." (emphasis in original).

{26}Note the similarity to attempts to determine whether extra-terresstrial contact with earth has taken place in the past. Says Carl Sagan, "convincing would be a certain class of artifact. If an artifact of technology were passed on from an ancient civilization -- an artifact that is far beyond the technological calpabilities of the originating civilization -- we would have an interesting prima facie case for extraterrestrial visitation." (emphasis in orignal). The Cosmic Connection, 1973. Garden City, NY: Anchor Books, p. 205.

{27}A fanciful story about the search for extraterrestrial intelligence (SETI), but accurate as to the procedure, is Contact by Carl Sagan, 1985. New York: Simon and Schuster.

{28}Hume's argument from "uniform experience" was quite general, finding application in science and religion. David Hume, the skeptic, used the argument against miracles. "There must, therefore, be a uniform experience against every miraculous event." Enquiry, p. 491.

{29}Michael Polanyi, August 21, 1967. "Life Transcending Chemistry and Physics," Chem. & Engr. News, p. 54.

{30}S. W. Fox and K. Dose, 1972. Molecular Evolution and the Origin of Life, San Francisco: W. H. Freeman.

{31}M. Eigen, W. Gardiner, P. Schuster, and R. Winkler-Oswatitsch, 1981. "The Origin of Genetic Information," Scientific American 244(4), 88.

{32}G. Nicolis and I. Prigogine, 1977. Self-Organization in Nonequilibrium Systems, New York: Wiley Interscience.

{33}A. Babloyantz, 1986. Molecules, Dynamics, and Life, New York: John Wiley & Sons, Inc.