Could Life Arise by Chance?

January 9, 2021


To give some idea of what exactly is involved in supposing that life could have emerged by random combination of chemicals in a primordial soup, let us imagine that this soup covered the entire surface of the earth to a depth of one mile. We shall divide this volume into tiny cubes measuring one angstrom unit on each side. (An angstrom unit is about the size of a single hydrogen atom.) Let’s also assume that the soup is extremely concentrated, so that reactions are taking place within each of the cubes within the soup.

Now, in the expectation of obtaining the simplest possible self-reproducing organism, let the reactions take place a billion times per second in each cube. And let’s further assume that the reactions have been going on for 4.5 billion years, the estimated age of the earth.

As we have seen in the accompanying article, scientists Fred Hoyle and Chandra Wickramasinghe have estimated that the chance of obtaining the simplest self-reproducing system by random combination of molecules is at best somewhere in the neighborhood of 1 in 10 to the power of 40,000 attempts. But if out of extreme generosity we reduce the required number of proteins from 2,000 to only 100, then the probability is still 1 in 10 to the power of 2,000.

Now, if you add up all the possible attempted billion-per-second combinations in our hypothetical primordial soup, you wind up with only 10 to the power of 74 throws of the chemical dice. That means the odds of getting the required self-reproducing system out of our soup would be 1 in 10 to the power of 1,926. We wouldn’t expect that to happen in the entire course of the earth’s history!

Of course, a diehard gambler might say it’s highly unlikely but it just could happen by chance. But this is a completely meaningless use of the word chance. In order for a statement about an event with a nonzero probability of happening to be meaningful, we would have to observe enough repetitions of the event to establish a statistical pattern. Only this would allow us to say, “This event has probability p of happening.”

For example, we say that when we toss a coin there is one chance in two that it will turn up heads. This probability is established by examining the behavior of the coin over several hundred trials. Now, if you have an event with a probability of one in a million, it would take hundreds of millions of trials to establish this. And if the event has an estimated probability of 1 in 10 to the power of 2000, you would need many times that number of trials. The basic point is this: What is meant by a probability of 1 out of 10 to the power of 2000 is that a certain statistical pattern corresponding to this figure will be observed over the required vast number of trials. If there is no possibility of performing these trials (as is certainly the case here), then there is no meaning to saying an event happens with that very small probability.

On this planet, as we have seen, you can only have a maximum of 10 to the power of 74 trials. Now, we can be extremely generous and grant the chemical evolutionists that the trials can be taking place in primordial soups on as many planets as there are atoms in the entire universe—about 10 to the power of 80 . Then you get a grand total of 10 to the power of 154 trials—still an infinitesimal number compared to 10 to the power of 2000. The conclusion is simple. It’s meaningless to talk about the origin of life in terms of chance. To say it happened by chance is just the same as saying it happened, and we already know that. In that case, all we can say is that life is a unique event.

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