4. Some Thoughts on Science and Religion
Written August 2007
( This essay is adapted from one which was published in Transit, the magazine of Cleveland and Darlington Astronomical Society, in September 2007. The previous issue had included a short article by Phil Plait, author of the Bad Astronomy blog, on the definition of a scientific theory, entitled “A scientific theory is much more than just a theory”. )
Phil Plait recently wrote on the definition of a scientific theory ( “A scientific theory is much more than just a theory” ). He uses the example of creationists who try to dismiss evolution by saying that “it’s just a theory”, and correctly says that those who use this argument either don’t understand, or conveniently choose to ignore, the scientific meaning of the word “theory”. I would like to elaborate on this theme.
As Plait says, a law describes something which happens in the natural world, based on observations, and a theory attempts to explain why it happens. They are not the same thing; a theory does not “become a law” when it’s proved. In fact, strictly speaking, a theory can never be absolutely proved to be correct; all we can say is that it’s supported by the evidence, and has passed all the tests applied to it. For example, we can be pretty confident that Einstein’s Theory of Special Relativity is correct, because it has passed every rigorous experimental test which has been applied to it for 100 years, with the observed results matching those predicted by the theory to better than one part in a billion. But we can never be absolutely 100% certain that it will continue to pass even more accurate tests in the future.
The important point, however, is that a theory can be proved wrong! If a theory happens to be wrong, then it will, sooner or later, be proved wrong, by finding observations which can’t be explained by the theory. This is how the scientific method works; a theory is formulated to explain the known facts and observations, then experiments are designed to test the theory. If an observation is found which doesn’t fit, i.e. the observed outcome of an experiment doesn’t match that predicted by the theory, then the theory is wrong, and must be modified so as to explain the new observations.
My point is that this is precisely what defines a scientific theory – it has to be testable, or as scientists say, falsifiable. That is, it must be possible to test the theory against observations, so that if it’s wrong, it can be proved wrong. In fields outside science, there are many examples of so-called “theories”, which are, in the scientific sense, nothing of the sort. The most obvious examples are the so-called “conspiracy theories”, involving UFOs, the alleged faking of the Apollo landings, the death of Princess Diana, etc. etc. Every “conspiracy theory” is by definition untestable, since no matter how much evidence is presented, which proves such a “theory” wrong, its supporters will simply claim that the evidence was itself faked, as a further part of the conspiracy.
( As a priceless example, some 24-carat loony once appeared on a TV programme about UFOs, claiming that we are being visited by aliens on a regular basis. His pet “theory” was that the visitors’ spacecraft “are able to disguise themselves as ordinary aircraft”! How’s that for a “theory” which can’t be proved wrong? )
The same, of course, most certainly applies to religion, and especially to the claims of creationists! The rational among us can present any amount of evidence which proves the age of the Earth, but a creationist will respond by saying, “The scientists have got it wrong; they’ve misinterpreted the evidence”. Hmm, now let’s see… the ages of rocks are determined by radioactive dating; the underlying physical process, radioactive decay, is so thoroughly understood that it’s utilised daily in manufacturing ( e.g. luminous paint, smoke alarms ) and medical procedures ( e.g radiotherapy to treat tumours, barium tracers ), the Voyager probes travelled across the Solar System powered by it, and millions of people routinely entrust their lives to heart pacemakers powered by it!
Some have even gone a step further, and claimed that “God has deliberately planted false evidence, to test our faith”! In other words, the entire Universe is a huge practical joke; their egomaniac God created it 6000 years ago, but then invested vast amounts of effort in making it look as if it’s billions of years old – just to see whether we humans will continue to believe in him, when confronted with overwhelming evidence of his non-existence! ( Rick Fienberg, the Editor of Sky and Telescope, countered this by presenting the alternative “theory” that the Universe was created this morning, and each of us has just popped into existence, just as we are right now, with all our knowledge of history, and our memories of our lives up to now, falsely implanted in our brains. Think about it; this is no more ridiculous, and no less falsifiable! )
As Mark Twain said, “Faith is the ability to believe what you know not to be true.”
Those who know me may find this hard to believe, but I have a good friend who is a fundamentalist Christian and a creationist – the kind who actually believes that everything in the Bible is literally true, and that the Creation really happened 6000 years ago. And even more unbelievably, we have actually managed to discuss such matters in a ( relatively! ) civilised manner. He claims that creationism is “a valid scientific theory”, as an alternative to evolution and the Big Bang. It is not! From what I said above, it’s obvious that creationism is not a theory at all, in the scientific sense, as it is, again by definition, not falsifiable!
The same goes for any “explanation” of the Universe involving God, or any other supposed “supernatural” being. We can say that such and such a mythical event could not have happened, because it violates the laws of physics; the “faithful” will reply, “So what? God is allowed to violate the laws of physics!”
Returning to Plait’s example of evolution; some creationists have tried to tell us that the Theory of Evolution is not testable. The theory is supported by the fossil record; fossils of various organisms are found in particular rock strata, which correspond to specific periods of geologic time ( remember that the ages of the strata are determined by radioactive dating – a physical process which is completely unconnected with evolution or biology ), which enables us to create a “timeline” of evolution, showing that certain organisms existed before other more complex ones. But as the fossil record is incomplete, creationists claim that the gaps in it make it unreliable, as there is no absolute proof of one organism evolving from another. No, there isn’t – but the evidence we do have is enough to convince most rational people that evolution is the most likely explanation. ( As Richard Dawkins points out, this “gaps in the record “ argument is analogous to saying that a jury can’t convict a person of murder, unless they are presented with a complete record of the accused’s every action, at every second of his life prior to the crime. )
More importantly, the creationists demand to know how the Theory of Evolution could be falsified; they claim that there is no hypothetical evidence which would convince scientists that the theory is wrong. But of course there is! If the theory was wrong, then there would be a blindingly obvious way in which it could be falsified. If a single fossil were ever to be found in the wrong rock stratum – in a layer corresponding to a time long before that particular creature is known to have existed – then that would prove the entire theory wrong, wouldn’t it? But of course, no such anomaly has ever been found, so the theory survives scrutiny.
I now come to my final point. One thing which I can never understand is how some people can profess both to be scientists and to believe in God! Some try to tell us that science and religion are somehow “compatible” – but they are not! From what I’ve said in this article, my reasons for saying so should now be obvious. Science and religion can never be compatible, as they are founded on completely opposing principles!
Firstly, religion ( and I’m talking here about the concept of religion in general, not any specific one ) is based on the concept of “sacred truths”; when a Christian ( or Jew, Muslim, etc. ) says that he “believes” such and such, he is actually saying “I stubbornly insist that this is the truth, and no amount of evidence will ever convince me otherwise”. Science, by contrast, is based on the principle that there is no such thing as a “sacred truth”; a theory is regarded as correct, only until such time as it is proved wrong by evidence.
Secondly, science is based on the principle that everything in nature can be described by natural laws ( remember, laws describe nature, and theories attempt to explain it ); in any given situation, given a knowledge of the laws and the initial conditions, the outcome can be predicted. Conversely, religion relies on the concept of “the Supernatural” and “miracles” – the notion that God ( or gods ) somehow exists “above” or “outside” the natural world ( and I defy anyone to explain exactly what “outside” means in this context! ), and is not subject to the natural laws of the Universe, but can violate them at will. This means that events in the natural world can’t be predicted in accordance with the laws of science – and therefore, that all scientific investigation is pointless!
Furthermore, while the entire purpose of scientific investigation is to fill gaps in our knowledge and understanding, religion teaches that there are things which we are not meant to know – we are not permitted to “know the mind of God”, and have no right to try ( despite the fact that much of organised religion is dictated by leaders who implicitly claim to do exactly that! ). The two are, by definition, incompatible, and always will be.