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Our future, our universe, and other weighty topics


Tuesday, September 25, 2018

Barash's Poor Logic on Cosmic Fine-Tuning

Our universe seems to be incredibly fine-tuned to allow the existence of biological organisms such as ourselves. Against all odds, the fundamental constants have values that allow the existence of long-lived stars, planets and living beings. Make minor changes in any of a dozen places in the universe's fundamental constants and laws, and observers such as us would be impossible.

An example (one of many discussed here) is the exact numerical equality of the absolute value of the proton charge and the electron charge. Given that each proton has a mass 1836 times greater than the mass of each electron, we would not at all expect these two fundamental particles to have electric charges that are exactly equal or exactly opposite. But according to modern science the electric charge of each electron in the universe is the exact opposite of the electric charge of each proton in the universe. The equality has been proven to be an exact match to at least 18 decimal places. We would not expect a coincidence like this to occur in 1 in a trillion random universes. The scientist Greenstein has stated that if this coincidence did not exist, planets could not hold together, because the electromagnetic repulsion between particles in a planet would totally overwhelm the gravity that holds the planet together (electromagnetism being a fundamental force more than a trillion trillion trillion times stronger than gravitation).


In Aeon magazine we recently had an evolutionary biologist named David Barash do his best to sweep under the rug the gigantic reality of cosmic fine-tuning. His “Anthropic Arrogance” essay is a grab bag of points that do not add up to any forcible objection to claims such as, “Our universe shows life-favoring characteristics so fantastically improbable that we should suspect a grand purpose behind its physical reality.”

Barash tries to raise doubt about the topic by quoting Einstein's statement “What really interests me is whether God had any choice in the creation of the world?” He states the following:

Note that Einstein was asking if the deep laws of physics might have in fact fixed the various physical constants of the Universe as the only values that they could possibly have, given the nature of reality, rather than having been ordained for some ultimate end – notably, us. At present, we simply don’t know whether the way the world works is the only way it could; in short, whether currently identified laws and physical constants are somehow bound together, according to physical law, irrespective of whether human beings – or anything else – eventuated.

But it is not at all correct to claim that “we don't know whether the the way the world works is the only way it could.” We do know exactly such a thing. We know, for example, that each proton has a mass 1836 times greater than each electron, and that the electric charge of each proton is the exact opposite of each electron. There is no a priori reason why such numbers could not have been totally different. And so it is with all of the fundamental constants of the universe. The hope occasionally expressed by physicists (that they might one day have a super-theory that explains all the fundamental constants and laws) is just a fantasy hope, kind of like some child saying, “One day I hope to own a marble mountain-top castle in Spain.” There does not exist any theory showing why any of the fundamental constants could not have had a vastly different value.   In the most unlikely event that physicists ever produce such a “this explains it all” theory, then appealing to such a thing may have some force; but until then, appealing to such a highly improbable possibility has no force.

Barash then resorts to a quite ridiculous argument sometimes made, that the universe isn't so fine-tuned for life because most of it is inhospitable to life. He says, “The stark truth is that nearly all of it is incompatible with life – at least our carbon-based, water-dependent version of it.” True, since the majority of the universe is just empty space. But anyone familiar with gravitation will know that you can't have a life-bearing planet without most of a solar system or galaxy being empty space. For example, if the space of the solar system mostly consisted of planets, the mass of such planets would exert so much gravitational force that the atmosphere of the earth would be pulled into space, and no one could breathe (not to mention that you'd be pulled out into outer space whenever you walked outside of your door).

Barash then resorts to a completely fallacious “extremely improbable things are very common” argument often made when materialists discuss cosmic fine-tuning. He points out that if you shuffle a set of cards, the chance of getting that exact sequence is something like 1 in 10 to the sixtieth power. Similarly, he reasons, if you strike a golf ball, there are trillions of different positions where the golf ball could end up, each extremely unlikely. Barash states, “For us to marvel at the fact of our existing (in a Universe that permits that existence) is comparable to a golf ball being amazed at the fact that it ended up wherever it did.”

This type of reasoning is completely erroneous, for it commits the fallacy known as false analogy. The fallacy of false analogy is committed when you draw an analogy between two things that aren't similar. The reason why the average shuffled deck of cards is not comparable to a fine-tuned universe is that a fine-tuned universe is something that resembles a product of design, but a random deck of shuffled cards does not resemble a product of design. The reason why a randomly landed golf-ball is not comparable to a fine-tuned universe is that a fine-tuned universe is something that resembles a product of design, but a randomly landed golf ball does not resemble a product of design. It is therefore erroneous to claim that, “For us to marvel at the fact of our existing (in a Universe that permits that existence) is comparable to a golf ball being amazed at the fact that it ended up wherever it did” – for in the first case there is something that resembles design, and in the second case there isn't.

Barash continues the same witless reasoning by talking about the improbability of one particular sperm uniting with one particular egg to produce a baby. It's the same “extremely improbable things are very common” bad reasoning. He points out that since there are 150 million sperm in a man's ejaculation, it's very improbable that any one sperm would unite with an egg. This is also a false analogy, because all of those sperm are identical, so the uniting of one particular sperm with an egg does not resemble a product of design or even something terribly lucky. So it's a false analogy to compare such a thing with a fine-tuned universe that seems to resemble a product of design and has all kinds of “lucky coincidences” all over the place.

Below is a conversation that illustrates the fallacious nature of the type of reasoning Barash uses in this case:

Son: Bye, Mom. I'm going to Las Vegas, and I will gamble my college fund at the roulette table, continuing to bet all my winnings until I become a billionaire.
Mom: That's crazy – you're all but certain to lose it all.
Son: But Mom, haven't you heard that very improbable things often happen? Why, if I shuffle this deck of cards, the chance of getting that particular sequence of cards is one in a gazillion. So my chance of winning the billion isn't so low.
Mom: You silly goose! Only run-of-the-mill, humdrum improbable things happen all the time. Extremely lucky random events don't happen often.

The son's reasoning is entirely fallacious, because while there very often happens very improbable outcomes that are not lucky and do not resemble the product of design, it is extremely rare and unlikely to have a random outcome resemble a product of design. So the chances of him winning the billion is every bit as low as his mother thinks.

Barash then asks two rhetorical questions about an asteroid collision millions of years ago, and I may note that such questions do nothing to advance his case.

Barash then appeals to the possibility of the multiverse as an explanation for cosmic fine-tuning, the idea that there are a large number of other universes. The fallacy of such an appeal is discussed in detail in this post, in which I give six reasons why such an appeal is fallacious. The best reason for rejecting the multiverse as an explanation for cosmic fine-tuning is the simple fact that you do not increase the likelihood of any one random trial being successful if you increase the number of random trials. For example, your chance of winning a million dollars in a weekend at Las Vegas is exactly the same regardless of whether or not there are an infinity of universes filled with gamblers who gamble at casinos. So whether or not there are a vast number of other universes has no effect on the probability of our universe being accidentally habitable. If there are a sufficient number of improbable coincidences, adding up very forcibly to an appearance of design, we should suspect such design if we think there is only one universe; and we should suspect such design with exactly the same force if we think there are many other universes.


Bad reasoning about your chances at Las Vegas

Barash then has a long paragraph building on the statement, “Shanks suggests that the multiverse hypothesis ‘does to the anthropic Universe what Copernicus’s heliocentric hypothesis did to the cosmological vision of the Earth as a fixed centre of the Universe’.” In the paragraph he drops the names of Galileo, Kepler and Copernicus. But it's not an appropriate comparison, because the conclusions of Galileo, Kepler, and Copernicus were based on observations, and there are zero observations of any other universe. What we have going on here is the same rhetorical trick that I discuss in my post “When Scientific Theorists Use 'Prestige by Association' Ploys.” Barash is trying to give some credibility to the groundless notion of the multiverse by trying to draw a very strained association between the multiverse and the hallowed scientific names of Galileo, Kepler and Copernicus. We shouldn't be fooled by such a maneuver.

Barash then appeals to the possibility of extraterrestrial life-forms that can get by on conditions much worse than we have. But this possibility does nothing to weaken the case for cosmic fine-tuning. I can give an analogy to explain why. If I come to a log cabin in the woods, I may reason that it's too improbable that such a house could have appeared by a chance arrangement of falling logs, and that the house is probably the product of design. If you were there with me, you might say, “That's not true because an organism could have just used a lucky tree hollow as its home.” But that does nothing to defeat my argument. Similarly, if its incredibly improbable that long-lived stable sun-like stars could exist in a random universe (and it is for the reasons discussed here), the existence of conditions that allow such stars strengthens the case for cosmic fine-tuning, regardless of whether some organism could barely get by living on planets revolving around stars that are less favorable for life, such as a star that periodically zaps its planets with high doses of radiation.

Barash then refers us to Lee Smolin's groundless speculation that attempted to combine the idea of natural selection with some weird speculation that collapsing black holes spit out baby universes. This wildly imaginative theory, known as the theory of cosmological natural selection, has not been widely accepted by physicists. We know of no evidence at all that black holes spit out new universes. And since universes don't have genes, and don't mate with other universes, it is preposterous for Smolin to be claiming that natural selection might come into play on the level of universes. Even if it were true that black holes did spawn child universes, this would do nothing to explain the fine-tuned characteristics of our universe, for the same reason that natural selection on planet Earth does not explain the appearance of very complex visible biological innovations (contrary to the claims of those like Barash).

The reason is the same in both cases: the fact that natural selection cannot occur in regard to some particular innovation until after that innovation appears. We cannot explain the appearance of something like a vision system in organisms by saying that such an innovation improved their survival and reproduction rate, because such an improvement (the same as a degree of natural selection) would not occur until after such a biological innovation first appeared; and a consequence that follows something is never the cause of that thing. For similar reasons, natural selection could not be the cause of some universe being fine-tuned. The idea of yanking natural selection from the biological world and trying to fit it into the vastly different world of cosmology makes no more sense than trying to apply Freudian psychology to a discussion of colliding subatomic particles.

Next in Barash's essay he reminds us of the very surprising fact that at the end of Carl Sagan's novel Contact, scientists found that after computing pi (the ratio of the circumference of the circle to its radius) to many additional digits, the scientists found a gigantic circle embedded within the digits of pi. In Sagan's novel this discovery is treated as proof that the universe had a designer. This ending was omitted from the movie of Contact. I'm not sure why Barash is bringing this up. Perhaps he is trying to suggest that scientists finding something suggesting the universe is designed belongs only in fiction. But it suggests that this very influential scientist (Sagan) was not too averse to such a possibility, so it does nothing to help the case Barash is trying to make.

In his last paragraph Barash builds on his previous attempts to associate the idea of cosmic fine-tuning with a claim that humans are the center of the universe, or that the universe was designed for humans. But there is no necessary association between the two, and few people promoting the idea of cosmic fine-tuning claim that the universe was designed for humans specifically, preferring the more general idea that the universe may have been designed for intelligent observers. So in this regard Barash is attacking a straw man. Someone can believe that the universe was designed for life, and that there are numerous different types of intelligent life forms scattered across the universe. You can believe that without believing that humans are unique, and without believing that humans are the most advanced biological organisms, and without believing that humans are the centerpiece of the universe.

So you may have Copernican-style objections about humans being the centerpiece of the universe, but that does nothing to defeat or discredit the idea of cosmic fine-tuning. Whether the universe was fine-tuned for living observers, and whether man is the center of the universe or the most advanced organism in the universe are two entirely different questions. The title of Barash's essay is “Anthropic Arrogance.” But there is nothing arrogant at all about noticing a long series of extremely lucky coincidences and favorable facets of the universe's fundamental constants and laws, and suspecting that more than mere chance is involved.

After noticing the fallacy-ridden reasoning of evolutionary biologist Barash on this topic of the universe's fine-tuned physics, we should ask: in what other places have evolutionary biologists got away with fallacious reasoning? We should then go back and scrutinize their more doubtful statements, such as claims that vastly complex functional systems such as vision systems (more complex than a smartphone) can be explained by saying that they appeared because of accumulations of random mutations, a kind of “stuff piles up” explanation as vacuous as the explanation of “stuff happens.”

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