This is one of my old posts from when I wrote more often at DC:
We have had a resurgence in discussing evolution recently, thanks in no small part to the Creationist mental contortions of Creationbabble over on this thread. what this seems to show, to me at any rate, is that Creationists, and any shade of person who disbelieves the theory of evolution, simply do not understand the philosophy behind it.
In short, they just don’t get it. Let me explain.
The introduction for the ‘Evolution’ chapter in my last book, The Little Book of Unholy Questions, included the following piece. I think it neatly shows how genetic heredity from reproduction, as a mechanism, is pretty common sense when considering what would be needed for life to continue to exist. Since evolution is a byproduct of this necessary mechanism, then evolution is unarguably a fundamental aspect of our existence.
Evolution, in recent years, has been put firmly back in the limelight. Just when Darwin, in his grave, thought that the general public had seen the light and accepted his wise words, the Creationist movement came to town and ruined everything. To me, evolution is a sound, simplistically elegant theory. It is borne out by huge amounts of data and evidence which, sadly, many disbelievers simply refuse to engage with or flatly deny. In order to harmonise two contrary ideas in their minds (belief in God and evolution), either one has to be massively reinterpreted or flatly denied. This is known as ‘cognitive dissonance’ and takes place on an extraordinary scale with regards to evolution and belief in God.
Francis Collins, once the head of the Human Genome Project, and himself a fervent Christian, has declared that the evidence for evolution is ‘no longer in question’ and ‘incontrovertible’[1], and that is simply from his own comparatively narrow field of genetics. When one takes into account geology, palaeontology, geography, biology, bio-chemistry, bio-cosmology, genetics, anthropology, behavioural psychology and so on, then the evidence is so wide-reaching that to deny evolution is to effectively bring down a massive pyramid of interlocking scientific fact.
Part of the problem with how many theists approach evolution is that they declare it is ‘just a theory’. This is the sort of tripe you hear on Fox News when they roll out another exceptionally right-wing denier who doesn’t actually know what they are on about. You see, technically speaking, everything that you know, or think you know, is ‘just a theory’. For example, the Theory of Gravity is just a theory, but do you doubt it enough to jump out of a fifth story window in a moment of science denial? No, because the evidence for gravity is abundant and immediately available first hand. Unfortunately, evolution is a process that takes millions, even billions, of years and is inherently more difficult to observe over a short timescale. But the evidence is there. There are millions of fossils, there are archaeological findings that evidence the migration of man out of Africa, there is the cross-breeding of animals and plants that we do in our own back gardens, and there is DNA, amongst many other things.
To get back to the point of it being ‘just a theory’ though, let us actually look at what a fact is. In fact (pun intended), the only thing we know to be indubitably true, that we cannot doubt at all, is the fact that ‘I exist’. René Descartes[2] came to the conclusion that you can doubt everything in the world. I can doubt that the bin in the corner of my room is actually there; that it is actually an optical illusion. I can doubt that my fingers are typing this, inspiring the possibility that I am actually dreaming. However, the only thing that I cannot doubt is that I exist, because I am thinking. The act of doubting is itself proof that I (at least my mind or whatever signifies ‘I’) exist. I think, therefore I am. Genius in so few words. As a result, though, it means that, strictly speaking, we cannot prove anything, because we can only account unflinchingly for our own subjective minds.
This means that every scientific theory is simply that: a theory. There is no fact. It might happen that when I next drop my pen, it falls upwards, and we will have to reassess the theory of gravity. The theory of gravity, as we know it, is a descriptive rule that governs everything that we have seen so far, but it could happen differently at any time, and could have happened differently already without us knowing.
Consequently, we use the term fact in a slightly counter-intuitive manner. A fact becomes a thing that is supported by overwhelming evidence. However, it becomes arbitrary as to where to draw the line as to what is overwhelming and what is not. Yet, because Creationists have coined the phrase that evolution is ‘just a theory’, many less discerning onlookers think that it gives them to the right to easily doubt it as a theory, that it therefore cannot have superior supporting evidence, and (scarily enough) that it gives them the right to teach alternative theories alongside it that have far less evidence to support them. This is the same tack that many news channels adopt when presenting any news or scientific finding. Often, they feel obliged to provide an alternative view with the same amount of airtime (in other words give both views equal coverage) even though the alternative view might only be held by five crackpot scientists out of a hundred thousand.
We have coded the genome, we have mapped out the tree of life, we have an awful lot of fossils, and we undergo ‘artificial’ (how can anything carried out by man, a natural animal, be artificial?) natural selection by breeding cows / tomatoes / crops to be bigger and higher yielding, and still people insist on denying it. I challenge an evolution denier, when offered gene therapy to proactively cure a terminal disease they will get in their later life, to turn down the therapy on account of genes and evolution being ‘just a theory’. That would make them ‘just an idiot’.
It is worth looking at evolution in light of what is necessary for humanity, or any living organism, to exist. First of all, there must be a cycle to life. We must reproduce. Any life form that simply existed as a finite number would have to be impervious to danger, immortal, in order to sustain their population. Organisms will die from natural causes, and as a result, they must reproduce in order to keep populations stable, or grow populations (in other words, to exist). Once we establish that reproduction is essential, we can then establish other necessary conditions required for existence. It is a simple formula. In order for a species to exist, and to continue existing, the organism(s) must survive to reproductive age, and must be able to effectively reproduce. For example, if humans could only reproduce over the age of one hundred, and we lived, on average, to seventy-five, then we would die out as a species. This is unarguable. Even Creationists cannot argue against this, given that it is logically coherent, and evident in every organism around us. Put simply:
1) Life must undergo reproduction, since finite numbers of organisms would die off in time.
2) Therefore, organisms must reach reproductive age to exist as a species.
3) Upon reaching said age, organisms must reproduce effectively to survive as a species.
Now, taking this into account, we also know, incontrovertibly, that organisms, on conception, join the male genome and female genome of their parents together to make the new genome of the newly conceived organism. This itself can be a source of evolution, combining new variations of genes, particularly if the two parents have a wide variation in their genomes.
In another source of evolution, when cells reproduce, the DNA in them (the coding mechanism) is copied (replicated). Sometimes, these replications are faulty. A part can be lost, added or swapped. In 99% of cases, though, this is corrected by cellular DNA checking mechanisms. In 1% of cases, the change stays. This change can be split into roughly three characteristics. The change can produce a trait or physical change that is problematic for survival or reproduction (points 2 and 3 above). The changes can also be neutral, or beneficial to these needs. If, for example, an organism mutated a weakness whereby it could not cope with cold temperatures anymore, and reproduced so that this trait was prevalent across the species, and there was a very cold winter that year, then the species (or members with that trait) could die out as a result of that mutation. If, on the other hand, the mutation created a mechanism that was beneficial to coping with the cold, and an ice-age came about, then that organism and its offspring would be more likely to survive (exist) through that time. Mutations are happening all the time, and organisms change, and react to their environment (or don’t) so that they survive (or don’t). This is a very simplistic view of evolution, and it is far more complex, with additional mechanisms and areas into which I will not delve. Suffice it to say, it seems to me to be a rather self-evident and simple process whereby very simple organisms gradually, over billions of years, have morphed into more complex and more varied species. Et voilà, homo sapiens sapiens arrives, via a common ancestor that we share with other primates (no we are not evolved from the apes on earth now, as is often cited, but we are all evolved from a common ancestor, for which there is much proof[3]).
[1] Taken from an interview with Robert Lawrence Kuhn for Closer to Truth (http://www.closertotruth.com/video-profile/Do-Science-Religion-Conflict-Francis-S-Collins-/463 retrieved 28/11/2011).
[2] The famous 17th century French natural philosopher whose name inspires ‘Cartesian’ philosophy.
[3] The oft cited Creationist mantra that we have evolved from monkeys / chimpanzees etc. makes me very angry. It is incorrect and espoused by utter dolts.
Hopefully, this will start to put to bed those Creationist mumblings about evolution. Face it, biblical Creation is ad hoc and unevidenced. Evolution is neither.