Saturday, 7 August 2010

Does evolution disprove God? (1)

Last time we saw that a theistic outlook on life is not incompatible with a scientific one. In fact, they gel quite nicely. This time we're going to discuss something rather more juicy. We're going to see whether a particular scientific theory - the general theory of evolution - gives theists an intellectual problem to consider. It is certainly true that of all the reasons skeptics often give for not believing in God, evolution ranks rather highly. But what exactly is the blow that evolution brings for the theist?

Before we recklessly dive into the question we need to break the issue down. As far as I can see, the broad question of theism's relation to evolution can be split into three lines of inquiry. Firstly, we should ask whether evolution is true. Secondly, we should ask whether, if true, evolution poses a challenge to basic theism. Thirdly, we should ask whether, if true, evolution poses a problem for specifically Christian theism (given the interests of this blog). In this entry we'll look at the first question.

Burn the heretic?

Many will consider me frighteningly fanatical, enormously ignorant, or horendously dishonest for even posing the question of whether evolution is true or not. Why is this? Well perhaps the evidence for evolution is so strong that in fact, accepting it is always the most rational choice for a person with the relevant facts at hand, and as it happens, the modern Brit does have such facts at hand. Even so, the shear horror displayed at the slightest doubt of evolution's truth is surely an exaggerated response, cultivated out of an (understandable) fear of mindless religious fanaticism. It seems clear to me however that with a question so bound up with important matters such as the origin and purpose of humanity - of ourselves - we have a right to have a little breathing space to voice any doubts we have even if these doubts are returned with a staunch assurance of evolution's truth. So let me breathe a little and a take a bit more of a personal stance in addressing this question.

I was a convinced evolutionist once. Then I was a convinced special creationist (I believed that God miraculously created all the basic kinds of creatures in the world). Now I'm somewhat agnostic on the matter. I'm not a scientist, and being so drastically removed from a subject I can claim even the most minor expertise in, I'm not going to tell you what the scientific facts are. I'm going to share some reasons as to why I personally have some reservations as to evolution's truth and then I'm going to talk about the nature of science so as to help you make a more informed decision for yourself.


The general theory of evolution states that every creature alive today is the result of millions of generations of ancestral creatures who had random genetic changes (produced by mutations or some similar mechanism) which conferred some survival advantage (or at least weren't enough of a hinderance to result in a creature's death before reproduction) and were passed down. So it goes that dinosaurs gradually accumulated mutations which produced wings and feathers, and these mutations proved beneficial over those who didn't have the mutations, so dinosaurs eventually evolved into birds. And similar stories account for all the variance of life we observe.

Nobody can reasonably doubt that creatures do undergo changes from generation to generation. What I (and others) doubt is the potential the mechanisms that produce these changes have for certain large scale changes. When do discussions about evolution really detail how a gradual change could be made from gills to lungs or cold-blooded to warm-blooded systems or any other significant changes? More puzzling yet is how sexual organs could have evolved from asexual reproductive methods. The sorts of changes involved would certainly be hazardous to the creatures who underwent them.

When I've raised these doubts in the past the response often given involves an account of why the trait which emerged was ultimately beneficial. This I do not doubt, but showing that a trait is beneficial is not the same as showing that a trait evolved or how it evolved. Even if it's not impossible, is it probable? In addition, given how sketchy our speculations are as to how consciousness emerged and as to how chemicals arranged themselves into the first living thing (which is technically the matter of abiogenesis rather than evolution but they are both wrapped in a similar over-arching narrative) I don't feel irresponsible in withholding some certainty about evolution as a comprehensive theory of life.

Anyway, even if I'm a fool and evolution is a dead cert' (or is at any rate, true) there sure are a lot of bad arguments put forward for it, and certainly a lot of bad arguments masquerading as science generally. Let's cut through the fog ...

Separate yer philosophy from yer facts

Looks like Benny has found himself in another tight spot ...

Pip: Funny, you know last time we chat, and you said that you're interested in science?
Benny: Yeah, I'm not that forgetful.
Pip: Well it seems your love is rather misplaced as a theist!
Benny: Oh?
Pip: Didn't you know? Science has proven that religious beliefs are just a misapplication of our evolved ability to understand the minds of other creatures.
Benny: Woah. Urm, really? Sounds like bad news for theists like myself.
Pip: Yup, it's true I have the paper that proves it right here. The study showed that people of all sorts of different religious backgrounds all use the same part of the brain to form beliefs about God's intentions. It's the same part we use to form beliefs about human intentions.
Benny: Lemme see that paper ...

This conversation is actually based on a recent experience I had with a skeptic on a debate forum. He too claimed that science had proved that religious beliefs were malfunctional in this manner and linked to a paper which he believed supported these claims. You can read the paper here. But what the skeptic and Pip (and the paper's author) haven't done is distinguish the facts from how those fact have been interpreted.

There are some parts of science which are essentially philosophically neutral. Measuring the distance from the earth to the sun, seeing what temperature water boils at, and calculating the speed of light are all such examples. We consider that you'd reach the same conclusion about these things regardless of your religious stance. But not all of science is like this (or at least certainly not everything that is passed off as science is).

Imagine (to loosely borrow an example found in Reason For The Hope Within) that you return home to find your house in tatters and your super-expensive television missing. You're a bit stunned and you aren't sure what to make of it. But you have two friends with you, and they both have their own explanation. One of them tells you regretfully that you have been burgled and your TV has been stolen. Your other friend tells you a somewhat cheerier account (she is something of an optimist). She remarks that possibly your neighbour scared the thief and took your TV into her house in case anyone else came in and stole it before the police arrived. Both interpretations fit the evidence. But they can't both be true ...

Naturalism. It's everywhere.

Sometimes science works like our example above. We all have the same facts but it's possible to interpret them in more than one way. In the buglery scenario, a cynic and an optimist will likely interpret the evidence in different ways. In some scientific matters, a theist and an atheist (or naturalist) will likely interpret the evidence in different ways. Currently it is far more popular and 'academically acceptable' to interpret the evidence in a naturalistic outlook. Philosophical naturalism is the belief that the natural world is all that there is, that there are no divine or supernatural beings of any kind. Naturalistic interpretations dominate scientific discussions at the moment. In fact naturalistic interpretations are often conflated with actual scientific data. This is a gross error that all of us must guard against. It would be like taking your optimistic friend's account of the burglar story as the observed fact, when actually that story is only a possible interpretation of the facts. This is the error that Pip made and the research paper made.

The facts of the paper (the things which have actually been observed) are that religious beliefs pertaining to God's intentions as a person are handled by the same part of the brain that handles beliefs pertaining to the intentions of human persons. Now see how these facts can be interpreted in two completely different ways ...

Naturalistic interpretation: human beings gradually evolved parts of the brain that allow us to consider what other people are thinking and feeling. Because this function of the brain isn't perfect it sometimes over-reaches and forms people-related beliefs about things that aren't people. People frequently observe things occurring in nature, like earthquakes, and they wrongly conclude that there is intent behind these things. People label the source of this intent as God.

Theistic interpretation: God is a personal being and through some process created humans with the capacity to relate to other beings by allowing them to consider what other people are thinking and feeling. Because God is a person, the part of the brain that enables this is also a perfectly appropriate tool for forming true beliefs about God himself.

So Pip was quite mistaken. 'Science' has proven nothing of the sort that she claimed. One must already accept naturalism to accept her conclusions. And since Benny is a theist he can go on his merry way. When thinking about the truth of evolutionary claims for yourself, make sure you distinguish the facts from the philosophy!

For the Christian, I consider Alvin Plantinga's advice very sound for discerning what to think about evolution. You can read his article 'When Faith and Reason Clash: Evolution and the Bible' over here. I also recommend his two part paper attacking the prevalent view that naturalism is a necessary assumption of science which can be found here and here.

Next time we do a bit of 'damage control' and see what would follow for theism if evolution were true.

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