1 Evolution versus creation: science and non-science
Science aims to extend our understanding of natural phenomena through testing of explanatory hypotheses by reference to hard evidence. It is not concerned with ideas that cannot be tested in this way, such as subjective opinions (for example, what is good or evil, beautiful or ugly) or religious beliefs (about, say, 'the meaning of life' and the existence of gods or spirits), though we will return to ideas like this at the end of this free course. The remit of science was eloquently summarised by Judge John Jones III in his judgement on a case heard in Dover, Pennsylvania, in 2005, involving the teaching of evolution in schools (Kitzmiller v Dover):
To be worthwhile, moreover, a scientific theory must do more than just 'be testable': it should successfully explain a wide range of phenomena that would be unintelligible or inconsistent under alternative hypotheses. On these grounds, the modern theory of 'variational' evolution, which combines Darwin's theory of evolution by means of natural selection with the discoveries of genetics, is resoundingly successful. Not only is it entirely naturalistic, such that every component can be (and has been) tested, but it also explains a remarkable variety of biological phenomena, including some that would otherwise seem positively inexplicable. The theory elucidates the diversity and distribution of organisms in space and time, the origins and nature of adaptations (their appearance of intricate design, but common lack of perfection), the existence of shared inherited characters, convergence and vestigial organs, the origins of species, including our own, the natural history of diseases, and even the way our minds work. As one of the leading evolutionary biologists of the last century, Theodosius Dobzhansky (1900-1975), remarked:
By contrast, the hypothesis of special creation not only flies in the face of the evidence, in so far as it can be tested, but in consigning the creative process to the unknowable the hypothesis doesn't explain anything beyond the mere existence of species. So it is not only a false hypothesis, but a vacuous one. And finally, its unverifiable supernatural element (the purported 'creator') puts it beyond the purview of science in any case.
This distinction between evolutionary science and creationist non-science is of more than just academic importance. Predictions concerning the impact on life of rapid climate change and other perturbations of global environments, as well as proposals for mitigation, crucially depend on a sound theoretical framework. For the reasons given above, special creation cannot be accepted as an alternative scientific theory on an equal footing to modern evolutionary theory, and so it has no legitimate place in any science classroom. It is in this context that the question of what qualifies as science, or not, has on a number of occasions come under legal scrutiny, especially in the United States, where a vociferous lobby of fundamentalist Christian creationists has repeatedly attempted to force their doctrine onto school science curricula at the expense of sound biology teaching. Fortunately, so far, their efforts have been checked by a number of astute legal judgements and unmasked for what they really are - covert attempts to introduce religious teaching into science classes, where it not only has no legitimate place, but would actually contravene US Constitutional law. Unfortunately, similar legal safeguards against the subversion of science education seem to be lacking in Britain.