The FIFTH MIRACLE: The Search for the Origin and Meaning of Life

Paul Davies is a theoretical physicist and a professor at Arizona State University. He is also a popular-science writer and in The Fifth Miracle, he writes about the origin of life. The book is accessible, but it left me with more questions than answers. Francis Crick won a Nobel prize for his work on DNA and for discovering the genetic code. Crick once claimed that the origin of life was “one of the great unsolved mysteries of science.” Every so often I read an article claiming that this puzzle has been solved but this book confirms that there is still much we do not know. Davies speculates on how life was created but lacks evidence for the options he discusses.We know that once life has been established, Darwinian evolution can take over. Unfortunately, before Darwinian evolution can start, a certain minimum level of complexity is required. But how was this achieved? Darwin did not explain how the first living thing came to exist. A letter to a friend indicated that Darwin believed that life was created on Earth in some sort of primordial soup or "warm little pond." This is the official version that still appears in school textbooks, but it appears to be wrong.Miller and Urey tried to create a primordial soup in a lab in 1952. They showed that amino acids could be easily produced by sending electric sparks through a mixture of methane, hydrogen, and ammonia, which was supposed to be like the atmosphere of the early earth. At the time this was thought to be an important advance in understanding how life began, but it appears to have been a dead end. The soup did not evolve into a cell, microbe, or anything resembling life. Just creating the basic building blocks of life does not explain how life was created. Being able to make a brick does not explain how the Empire State Building was built. However, I recently watched a PBS documentary where the makers seemed to imply that Miller had created life in a test tube. Davies is skeptical that purely biochemical forces could spark the leap from nonlife to life. Davies suggests that “something funny” must have also occurred. We seem to be missing a step in the process. However, Davies is careful not to invoke God, so it remains a mystery what that missing something is.The complexity of the living cell is immense, it has been compared to a factory in the degree of its elaborate activity. Each molecule has a specified function and a designated place in the overall scheme so that the correct objects are manufactured. Molecules are dumb and cannot think, so what is guiding them? Scientists have not been able to create a cell from scratch in a laboratory. The genetic code, with a few recently discovered minor variations, is common to all known forms of life on Earth. This suggests it was used by the common ancestor of all life and is robust enough to have survived through billions of years of evolution. The code is also incredibly complex, the human genome contains about 6 billion letters and 700 megabytes of data. Bill Gates has described DNA as the most complex computer program ever written.Crick suggested that life may be too complex to have been created in such a random way. Crick said that life was so unlikely, it was almost a miracle. If DNA is like a computer program, then programs usually have a programmer to provide the instructions. It is hard to believe that DNA was a lucky accident. The human genome has 6 billion characters, while the complete works of Shakespeare have about 900,000 words. There is an urban legend that if you have enough time and enough monkeys they would eventually reproduce the complete works of Shakespeare. Mathematicians have concluded that this is impossible. However, evolutionary biologist Richard Dawkins employed the typing monkey idea in his book 'The Blind Watchmaker' to claim that natural selection can produce biological complexity out of random mutations. There seems to be something wrong with Dawkins’s math.Davies points out that when he was a student in the 1960s the common belief was that we were all alone in the universe and life on Earth was a bizarre fluke. In the 1970s, Crick hypothesized that life may have originated elsewhere in the universe and arrived on Earth from space, this is called panspermia. The science fiction writers on Star Trek, as well as Ridley Scott in his film Prometheus, have used this as a plot device. The problem is that we have not discovered life elsewhere in the universe and there is no evidence of intelligent life anywhere other than on Earth. Davies is hopeful that intelligent life exists elsewhere, and therefore believes panspermia is a plausible theory.Davies believes that the discovery of rock-eating, volcanic microbes’ living deep within the earth’s geothermal vents, their temperatures rising well over boiling point, points to life existing in inhospitable environments. He believes that life probably started in a similar environment somehow. Replicating this environment in the lab did seem to produce some of the chemicals necessary for life, but it did not produce microbes. Davies believes that meteorites found in Antarctica suggest that life could have traveled to Earth via Martian asteroids. Three and a half billion years ago, Mars resembled earth. It was warm and wet and could have supported primitive organisms. If life on Earth started on Mars, what created life on Mars? If the Martian genetic code is the same as that on Earth could that mean that there is a universal genetic code? if so, who or what created it? The laws of physics are assumed to be the same throughout the universe if so, does all life in the universe use the same genetic code? Again, we do not know.Davies ponders whether life inevitably evolves to eventually become intelligent life. Do microbes eventually evolve into something that achieves consciousness? Davies argues that we have two conflicting views "the nihilistic philosophy of the pointless universe" as per Richard Dawkins, while on the other hand, we have "an alternative view, … a universe in which the emergence of thinking beings is a fundamental and integral part of the overall scheme of things. A universe in which we are not alone." In other words, our scientists do not know how or why intelligent life evolves. Why did we suddenly become very smart about 40,000 years ago? Why do humans have a language gene and monkeys do not?At the end of the day, we still do not seem to know much more than Darwin about the origin of life. We still seem to be stumbling around in the dark. The media tends to over-hype how far we have come. Today's origin of life scientists need funding for research and have come to resemble used car salesmen, they sound more authoritative than they are entitled to be. I recently listened to a talk where a scientist was confident he could create life in a laboratory if he was given enough money. The more we learn about the complexity of cells and DNA the more limited our knowledge seems. For obvious reasons, our scientists seem reluctant to admit that humans may not be sufficiently evolved or even smart enough to work out the origin of life.The Fifth Miracle was written in 1999. Davies published 'The Demon in the Machine' in 2019, this brings his thinking on the subject up to date. It might be a better starting point.

Davies, in THE FIFTH MIRACLE, intelligently criticizes the material-reductionist model of the origin of life. According to the current (secular) notion of the origin of life, by pure chance a conglomeration of molecules capable of duplicating got grouped together in conditions capable of supplying energy and raw materials for duplication. Somehow these molecules became so complex that they made the leap from merely being duplicated by proper external conditions to being able to encode the necessary information to create organs able to search for and imbibe energy and raw materials for themselves, and then the additional leap of manufacturing molecules able to repair errors in their replicating processes, to develop sense organs able to avoid danger and find something sexy to mate with, and to create works or art, literature, music, and science. All of this happened as a consequence of random errors in the replicating process, even though the overwhelming majority of those errors were detrimental or more likely fatal. These replicating errors were so successful that now zygotes, too small to be seen with a naked eye, can code sufficient information to develop into everything from frogs, dogs, humans, orchids, and redwoods. This is held to be true despite the fact that the complexity of the proteins and DNA molecules in the zygote is such that the probability that they could have formed by chance within the lifetime of the universe is essentially zero. Anybody who doubts that this is true will be snubbed by the mainstream scientific community as simply not bright enough to understand evolutionary theory. (Of course, the popular alternative explanation, Intelligent Design, is even harder to believe, and offers no evidence whatsoever). Davies summarizes all of the current notions about how molecules might have started replicating, but emphasizes that the ability to replicate is still a far cry from the ability to encode complex information, analogous to the difference between a plastic disc and the program recorded on the disc. He does not believe that the laws of nature as we presently comprehend them can account for this transition from hardware to software.Scientists typically get pissed off when people claim that evolution is an accidental process. It is not accidental because the molecules that developed into life and formed all of the variety of existing organism did so according to chemical laws. Ian Stewart, for example, says life is no more accidental than the growth of a crystal; both form by the operation of fundamental chemical laws. Life is therefore deterministic and will form in any environment supplying the necessary energy and raw materials. This explanation ignores the mind-boggling improbability that chemical laws would just happen to have the deterministic ability to develop into life. The very laws of physics seem to have been fine-tuned to make life possible. If life is not intrinsic to existence, then the existence of these laws is necessarily accidental. But if they are not accidental, then what is the alternative? Davies asks, "Might purpose might be a genuine property of nature right down to the subcellular level (p. 122)." Although biological processes appear to be purposeful, they are cannot be because purpose is impossible in the material-reductionist model of reality (which cannot possibly be wrong).Chemical laws can rearrange information as dictated by genomes; they cannot create the information of the genomes. "Life works its magic not by bowing to the directionality of chemistry, but by circumventing what is chemically and thermodynamically `natural (p. 255).'" Davies suggests complexity theory as a radical solution to how nature manages this. His proposal is that "information is a genuine physical quantity that can be traded by `informational forces,'" and that complexity is a physical variable with causal efficacy. This proposal is certainly abstract, and seems, like Ilya Prigogine's notion of order out of chaos, to be more of an observation than an explanation. It is also not a testable "theory," and therefore hardly a theory at all. Of course, the proposal that life arose by chance is equally untestable, and therefore hardly a theory at all, though this is typically ignored. On the other hand, given the "astronomical improbability" of life forming by chance -- even if one supposes that there is a multiverse to play around in -- Davies' proposal is far more plausible. Davies also speculates, from the observation that the dual wave-particle nature of the quantum corresponds to a hardware-software duality, that some sort of quantum-organizing process might be what is needed to explain the origin of informational macromolecules. This sounds possible, and even very probable to those of use who do not credit chance with miraculous prowess, but untestable.Davies does not delve much into the actual meaning of life, but he does imply that if it arose by chance it can have no meaning. Human intelligence can have no significance beyond its survival value, and the cockroach has far more survival potential than humanity. One consequence that emerges from the notion that life has intrinsic existence is that Darwin was wrong (my observation, not Davies's): The driving force of evolution is not "survival of the fittest," but the development of greater complexity, with the definite goal of eventually achieving a level of complexity capable of self-reflective intelligence. The proud boast that we understand nature so well that we know ourselves to be not quite as good as cockroaches is puerile arrogance disguising itself as modesty.Davies introduces no hint of anything spiritual or even noncorporeal in THE FIFTH MIRACLE. Possibly this is his own inclination, but if he had, the book would certainly have been blasted by mainstream scientists. It does follow, however, that if life has intrinsic existence, then consciousness existed in some sort of primordial form from the very beginning. It is even plausible that consciousness and matter are two aspects of the same thing. If this is true then it would hardly be surprising the universe is fine-tuned for make life possible.

A lot of intelligent, interesting and profound ideas. The best is the role of intelligence itself in shaping the future of the cosmos, not necessarily an all embracing intelligence on a "god" scale but rather each and every intelligent being is capable of affecting the future for good or bad. Of course he assumes that "intelligence! involves "free will": I agree with that but that part is not explored thoroughly.

This is very informative book. One must also read "The Origin of Life" from Paul Davies.

C'est à la fois passionnant et très prenant de suivre l'auteur dans sa recherche de l'origine et l'émergence de la vie. Beaucoup de questions, point de réponses. En cours de route, on découvre ou redécouvre la deuxième loi de thermodynamique et la théorie de l'information de Shannon.