God vs The Multiverse (Part 5: The Origin of Life)
Rabbi E. Feder, Rabbi E. Zimmer
We are going to make a short digression into biology and the problem (and attempted solution) of the origin of life. We want to make it very clear that we are not using the problem of the origin of life in our proof of God. We are relying upon the fine tuning of the constants of nature and the initial conditions of the big bang. The reason we are introducing the proposed solution to the origin of life is because multiverse physicists attempt to extend this type of solution to explain the phenomenon of fine tuning in the universe.
The 'origin of life' problem can be roughly expressed as an 'origin of something as complex and special as DNA' problem. A short historical and scientific background on the theory of evolution will help explain why the unsupplemented theory of evolution cannot explain the origin of life itself.
The key development which enabled the theory of evolution to emerge, was the discovery that the age of the Earth was much greater than scientists historically had evidence for. The expansion of the known age of Earth based upon geological evidence in 1785 by James Hutton, and then further developed by Sir Charles Lyell in his book, Principles of Geology (1830), opened up the possibility for a much deeper understanding of the complexity of life.
Charles Darwin's supplied this understanding with the theory of evolution, in his famous book On The Origin of Species (1859). The modern version of Darwin's theory which includes genetics, called Neo-Darwinism, was developed around 1950. It is a very elegant, simple theory that explains the wonderful diversity of life, and gives you an appreciation for how an amazingly complex cell can emerge from the information encoded in DNA. (We are not taking a stance on whether or not Neo-Darwinism is entirely sufficient and complete to explain all the facts about life. That being said, there is definitely something right about it.)
The essential element of biological evolution is the self replicator (DNA), which is something that makes near perfect copies of itself. The replicated copy is the next generation of replicator, which continues the process of nearly perfect replication.
It is necessary for the functioning of natural selection, that the process of replication not be perfect. Slight variations in each generation which arise from the "failure" to reproduce an exact replica (because of the occurrence of a mutation), are what allow the process of natural selection to act on those differences and select the fittest organisms for survival.
The key point is that it is intrinsically impossible to explain the existence of the first replicator itself (the first DNA molecule) through the theory of evolution. This is because evolution and natural selection only operate once a replicator exists. In a sense, the science of biology begins after the first replicating molecule comes about (given the proper properties of the environment. See the first comment below for an elaboration of this point.)
Many biologists speculate that there was another, long forgotten, yet simpler replicator that was the ancestor to the first DNA. This pushes the problem back to how the first replicator emerged, as any replicator which is sufficient for evolution to operate on, would probably be a highly complex entity.
This problem is known as the origin of life problem. Any solution to it bridges the gap between chemistry and biology (between the inanimate and the animate). The biological theory of evolution cannot solve this problem. Where did the first replicator come from?
The main approach to resolving this problem is by invoking luck (chance). Since you only need to get lucky once (after you have the first replicator, biological evolution takes over), it becomes more reasonable to speculate that perhaps it all started by a lucky break. While this might initially sound like a very forced answer, the weak anthropic principle (which we'll explain) elucidates why it might be a fairly reasonable solution.
It is important to clearly understand the difference between the strong anthropic principle, which we used to refer to a teleological explanation (in post 3), and the weak anthropic principle, which is a very different type of causal explanation. Once again, labels are not as important as concepts.
It is speculated that perhaps there is some way that some inanimate thing should accidentally combine with some other inanimate thing, and produce the first living replicator (an ancestor of DNA). Once we have DNA, the theory of evolution claims that the rest is just details. While the emergence of DNA by chance might seem highly improbable to occur, since there are many, many planets in the universe which are in theory hospitable to life, even something very unlikely may become probable given such a large number of possible tries.
A simple analogy makes this reasoning clear. If your odds of winning a lottery are one in a million assuming that you buy only one ticket, then your odds increase dramatically if you buy trillions of tickets. In fact, given enough tickets, your odds of winning become highly likely. If you win, you're not really as lucky as you may feel. The law of probabilities operates very efficiently when big numbers are involved.
Should someone ask, "maybe it is likely for life to randomly occur once, but what are the odds that it would be here on Earth?" To that, the weak anthropic principle is invoked. Essentially, it says that there is an easily overlooked, causal relationship between an intelligent observer and the development of life. Namely, life is a necessary condition in order to have an observer even ask the question about why life is here on Earth. Only on those planets that life exists, is it even possible to have observers, and therefore we should not be surprised to find ourselves on a planet with life. There aren't any intelligent beings on planets without life. By this line of reasoning, it is superfluous to invoke a teleological explanation (i.e., the Earth was designed in order to produce the first DNA) in order to explain life on Earth.
It is not necessary to know the precise numbers of planets vs. the exact odds of a DNA molecule emerging by chance. You just need to match them to roughly the same order of magnitude (basically, that they're "closely" matched). Should those odds be close to the number of planets, we would have a good explanation for how life started. The fact that we are on the one planet in which it did occur is obviously not a question, as the existence of life is a necessary condition for us observing life and asking the very question in the first place.
As of yet, it is still unclear that the number of hospitable planets suffices, given that science does not currently have a well established theory for a chain of progressively more complex replicators that lead to DNA. The odds of getting a DNA molecule itself seem greater than the number of hospitable planets in the observable universe; but it is conceivable that we may find evidence of a simpler replicator that will allow us to compare its odds against the estimated number of planets, which is known to be a very big number. (By the way, the multiverse theory solves this problem too, as it posits a nearly infinite number of hospitable planets.)
The key conceptual point to take away from this for the next post is that this type of reasoning only works because there are known to be many planets that are hospitable to life. Therefore, even though it is highly improbable on any particular planet for life to spontaneously generate by chance alone, it can become likely if there are enough possible planets for it to occur on.
This line of reasoning is inapplicable if there is only one known planet. It is not a good explanation to say that a highly improbable event occurred, given that there was only one try. Before scientists observed the many, hospitable planets, it was not reasonable to say that life originated from inanimate matter through chance alone. That is too much of a coincidence to accept!
(This reasoning is also implicitly contingent on the very reasonable assumption that whatever happens on one planet does not affect the results of a different planet. If the results on all the planets were correlated to each other in a way that whatever happened on one planet also occurred on all the others, it would be equivalent to having a trillion copies of one lottery ticket. This point is very obvious and we only mention it because it will be important in the next post.)
The next 10 minute video is about the origin of life by biologist Richard Dawkins. (It is a part 3 of 5. (Click here for Part 1, Part 2, Part 3, Part 4, and Part 5. We highly recommend the first 3 parts as Dawkins is one of the best teachers of evolution around. We've learnt a lot from him.) We will only be embedding Part 3, as it nicely transitions into stage two of our posts about the multiverse. Dawkins first summarizes the contents of this post. He then distinguishes between the Many Worlds Interpretation of Quantum Mechanics which is not relevant to the fine tuning of the constants, and multiverse theory that is relevant for the fine tuning. He then discusses how physicists try to explain the fine tuning with the weak anthropic principle and the multiverse, though he acknowledges that it is only a satisfying solution for fine tuning if there are other independent reasons for postulating the multiverse (which Dawkins believes there are).
(We will answer Dawkins' question of "Who designed God?" in stage three of the proof, when we explain the concept that God is One.)