by Thomas Dixon
Starting with the scientific case against ID, there are two related points to make. First, evolutionary theory can in fact explain the biological complexity which ID claims defeats it; second, ID is excessively negative, looking for gaps in evolutionary science but without providing a coherent alternative theory in its place.
Arguments about ‘irreducible complexity’ are a new form of a very old anti-Darwinian argument, namely that complex structures could not have evolved by natural selection because the intermediate forms containing only some of the parts would not have been adaptive. What use is a part of an eye, half a wing, or three-quarters of a flagellum? In general terms, evolutionists have been able to answer this objection by finding, either in fossils or in living species, evidence of intermediate structures that did exist and were in fact adaptive. In the case of the eye, Darwin himself listed various forms of eyes, from a small patch of lightsensitive cells to the complex ‘camera’ eyes of humans and other animals, showing how each was adaptive and could have evolved into the next in the series. Scientists now estimate that this entire evolutionary process could even have been achieved within a mere half a million years. Advantages were also conferred by the precursors to fully fledged wings. Feathers, for instance, seem first to have evolved as a form of insulation before being co-opted by natural selection to aid a quite different function – flight. It is harder to produce these scenarios in the case of biochemistry because, obviously, chemical reactions, unlike feathers, do not fossilize. However, using evidence from currently living species it is possible to reconstruct evolutionary scenarios. This has been done, for instance, in the case of the famous bacterial flagellum, which, it has been suggested, evolved through the co-option of a very similar existing structure (known as the type three secretory system) used by bacteria for injecting toxic proteins into the cells of their hosts. So the answer to the question ‘What use is a part of an eye, half a wing, or three-quarters of a flagellum?’, is ‘Light-detection, warmth, and toxin-injection, respectively’.
A second objection to ID concerns its negative character. This is another respect in which ID differs from Scientific Creationism. Creationists of earlier decades proposed an alternative theory which boldly, biblically, and patently wrongly asserted that the earth was only a few thousand years old, that geology could be explained by a recent worldwide flood, and that humans did not share ancestors with other animals. The defenders of ID, on the other hand, simply draw attention to what they claim are phenomena (such as the Cambrian explosion or the blood clotting cascade) that display too much ‘specified complexity’ to have evolved by mutation and natural selection, and at that point invoke their unelaborated concept of an intelligent designer, barring the way to further investigation. The ID theory makes no novel predictions beyond the failure of evolutionary science to explain these phenomena. It is not clear where ID theorists would draw the line between that which can be explained by evolution and that which needs an intelligent designer. And it seems likely that, in future, as good evolutionary explanations are suggested for their favoured examples, as has already happened in the case of the flagellum, the number of cases for which ‘design’ can be claimed will slowly but surely dwindle.
One of the main theological objections to ID follows directly from this last point. In claiming that supernatural intervention is required to explain a certain subset of natural phenomena for which a full evolutionary explanation may currently be lacking, ID theorists seem to be positing a ‘God of the gaps’ of the kind discussed in Chapter 3. As gaps in evolutionary science are filled with naturalistic explanations, God will gradually be edged further out. This tinkering God of ID, this God who seems to be an occasionally observable object in the natural world, found in our current ignorance rather than in our understanding, is no more attractive to theologians than to scientists – hence the thousands of clergy who have been moved to sign the open letter against ID mentioned above.
But is it science?
Judge Overton in the 1982 Arkansas case and Judge Jones in the 2005 case in Pennsylvania both declared that Creation Science and ID, respectively, not only contravened the First Amendment but were, in any case, not proper science. This is a common claim – that creationism and ID are not scientific because they fail to fulfil one or more criteria which characterize all genuine science. There are various candidates for such ‘demarcation criteria’. Some say that true science must be empirically testable, others that it must make ‘falsifiable’ claims, others that it must offer explanations only in terms of natural laws and natural processes.
Philosophers of science are much less optimistic than they were a few decades ago about the possibility of finding any really coherent demarcation criteria. It is accepted that many scientific claims – including many of the most interesting ones – are not directly empirically testable but only become so as part of a complex network of auxiliary theoretical assumptions and scientific instruments. For instance, a mathematical model of the Big Bang cannot be tested by direct observation, but only indirectly through predictions about the behaviour of measuring apparatus when a particular reaction is set off in a massive particle accelerator. Creation Scientists made very clearly testable claims about the age of the earth and the separate ancestry of all species. Although it is an unusually minimal and largely negative kind of theory, ID certainly can generate empirically testable claims too, such as the assertion that adaptive precursors will never be found for various specified processes and structures such as the blood clotting cascade or the bacterial flagellum. Creationists and ID proponents have regularly made testable claims. These claims have been tested and repeatedly found wanting.
It is also accepted that good scientists will often hold on to their theories in the face of inconsistent empirical evidence and seek to reinterpret that evidence rather than declare their theory ‘falsified’. There is not yet an evolutionary account which successfully identifies every single stage in the evolution of the flagellum (or in the evolutionary history of many other organs or biochemical processes), but that does not mean that scientists should declare neo-Darwinism to have been ‘falsified’. The modern framework of evolutionary theory successfully explains and unifies a huge body of evidence accumulated and interpreted over many generations. It makes sense of the fossil record, the geographical distribution of species, the physical similarities between related plants and animals, and the vestigial organs that testify to earlier evolutionary forms. Recent advances in genetic sequencing have provided a huge new mass of evidence which confirms evolutionary theory while identifying a whole new range of puzzles and anomalies. In the face of puzzles and anomalies a good scientist, especially when working with such a well-confirmed theory, does not declare their theory falsified, but designs new experiments and develops new theoretical models to solve those puzzles and resolve those anomalies. The central claims of ID theorists all seem to have been falsified. But in holding on to their theories and trying to provide an alternative interpretation of the evidence, they are only doing what all good scientists would do. A very significant difference, however, is that ID supporters lack any good reason for confidence in their original theory.
Testability and falsifiability are not satisfactory demarcation criteria. What about the insistence that proper scientific theories should be entirely naturalistic? This is a relatively new doctrine.
Neither Isaac Newton nor Charles Darwin, to take just two examples, felt that God had to be excluded entirely from their scientific accounts of the natural world. In scientific theories between the 17th and 19th centuries, God featured generally as a lawgiver rather than as a tinkerer, but God was not absolutely barred from professional scientific discourse until the later 19th century. In appealing to a supernatural cause as part of their science in the 21st century, ID theorists are certainly unconventional, eccentric, and out of step with recent practice, but that need not mean they are to be excluded from the realm of science altogether. There is no need for defenders of mainstream sc
ience to risk seeming ideological and doctrinaire by prejudging the kinds of entities that will feature in successful scientific theories in the future.
In short, opponents of ID who use the weapon of philosophical demarcation may be shooting themselves quite unnecessarily in the foot. In the United States, the pro-religious intent and effect of any policy mandating the teaching of creationism or ID will be enough to keep it off the statute book. There and elsewhere, scientists and theologians, as well as voters and judges, also have many good reasons to resist ID without straying into the fraught philosophical realm of demarcation.
Back to the classroom
The most recent slogan of the ID movement, echoing the calls for ‘balanced treatment’ of earlier decades, is ‘Teach the Controversy’. The publisher’s description of the ID textbook Of Pandas and People states that it ‘promotes a widely recognized goal of science education by fostering a questioning, skeptical and scrutinizing mindset’. Other ID proponents claim they are seeking to improve public discussions of science and promote a more inclusive and ‘controversy-based biology curriculum’. This is disingenuous. Of course science thrives on constant criticism, questioning, and controversy. Such controversies can be a very useful way to teach science. To the extent that ID theorists have served as gadflies or catalysts to evolutionary science, they have performed a valuable scientific function. However, ID is not really a movement for educational reform. The ‘controversy’ in question has not arisen from any substantial scientific disagreement but is the product of a concerted public relations exercise aimed at the Christian parents of America.
Even if we are charitable and allow that ID might be a kind of science, it is a dreadfully obscure and unsuccessful kind of science. If, in the future, ID became the basis of a serious and fruitful scientific research programme and thus converted a substantial proportion of the scientific community to its views, then it might be reasonable to discuss the inclusion of ID on a science curriculum (if First Amendment objections could somehow be overcome). At the moment, ID is supported by a tiny handful of very marginal scientific figures, is rejected by the rest of the scientific world, and appeals to a wider public for patently religious reasons. There is an almost endless list of interesting scientific and philosophical controversies that would be candidates for inclusion on a ‘controversy-based biology curriculum’. But many would be excluded because they were too technically demanding, too far removed from mainstream science, or too clearly manufactured by a special-interest group for political and ideological reasons. The debate about ID would fail on all three counts. In addition to the political, legal, scientific, and theological reasons for excluding ID from science classes, then, there are perfectly good educational ones too.
There is no genuine scientific controversy about the relative merits of evolution and ID. But creationism and ID do draw attention to genuinely controversial questions about the nature of science and its place in society: Should voters, elected politicians, judges, or scientific experts have the final say about what is taught in the science classes of publicly funded schools? Why has modern America proved such fertile ground for the growth of anti-evolutionary movements? Can God ever be discovered through scientific methods? Can testability, falsifiability, naturalism, or any combination of these, be invoked as viable demarcation criteria? Wherever comparative religion and the history and philosophy of science are taught, creationism and ID can profitably be studied. Indeed, if the effect of the continued exclusion of ID from the science syllabus is that its advocates start a campaign for the inclusion of these other subjects on the curricula of publicly funded schools, then some educational good may still come out of this peculiarly American controversy.
Chapter 6
Mind and morality
We have seen that religious responses to evolution in all traditions continue to centre on questions about human nature. How can human beings be created in God’s image, believers ask, but also be nothing more than improved apes with mushrooms for cousins? If human beings have physically evolved from lower forms of life, then at what point, if any, did the rational soul develop? Since the 19th century, scientific studies of the brain and mind have been providing further challenges to religious beliefs. If the soul is nothing but a product of brain activity, as science seems to suggest, does that not imply materialism, determinism, blank atheism? What place does such a view leave for belief in moral responsibility in this life or the prospect of rewards or punishments in the next?
For many people, it is these questions about mind and morality that drive the whole debate about science and religion. Believers resist the idea that human consciousness, morality, and even religion itself can be explained scientifically. If religious experience and human morality can be explained as natural phenomena, there seems to be no further need for supernatural accounts of such things. And those who promote such explanations often do so as part of an explicit campaign to show both that religious beliefs are mistaken and that science can explain their real origins.
This chapter asks what the implications really are of the scientific study of mind and morality. It also asks what ethical significance, if any, can be attached to scientific claims that human behaviours including altruism and homosexuality are natural. It ends by suggesting that science and medicine seem to have stepped into roles that were previously the preserve of religion, by defining and enforcing divisions between the normal and the deviant, and by using visions of the future to alter our behaviour in the present.
The soul and immortality
When scientists started to turn their attention to the human mind they were approaching a domain that had for many centuries been at the centre of religious life and thought. Not all religions include reverence for sacred scriptures, nor even belief in a creator God, but all religious traditions, East and West, teach that wisdom and salvation are to be found in the life of the mind.
Different words are used to refer to those sensations, thoughts, and emotions that are so central to the religious life. Historically the terms ‘mind’ and ‘soul’ have been the most generally adopted, sometimes used synonymously and sometimes with one being a subset of the other. ‘Self’, ‘spirit’, and ‘consciousness’ can similarly denote either a general or a more specific aspect of mental life. In the specialist literature there is little consensus about the exact meaning of these terms. However, it is certainly the case that the realities to which they refer are of particular religious concern. Religions teach individuals how to use spiritual exercises such as meditation and prayer, as well as ritual and liturgy, to achieve a state of greater enlightenment, spiritual awareness, and moral and religious strength. They also teach that each individual has a soul, the state and eternal destiny of which will be determined by their actions in this life.
There is a great variety of teachings about immortality, resurrection, rebirth, transmigration, or reincarnation that feature in various traditions. There are many disagreements and differences of emphasis even within and between the three monotheistic traditions, but there are some common elements that we can pick out. Judaism, Christianity, and Islam all teach that there will be some kind of life after death, and that it will take the form of either a bodily resurrection, the survival of a disembodied soul, or both. They also all teach that the nature of the afterlife will depend on one’s spiritual state. There will be a moment of judgement in which God will divide humanity into two categories, which are variously conceived of as the elect and the damned, the faithful and the faithless, or the righteous and the wicked. The chosen ones will spend an eternity of peace and joy with God, the unfortunate remainder will be punished. According to traditional interpretations of Christian and Muslim teachings, those who are not among God’s chosen will be consigned eternally to a hellish fiery pit. Ideas about hell have been less prominent in Judaism. According to some Jewish teachers, punishments in hell are only a temporary prelude to eternal bliss. In those traditions in which God does make a final and irreversible judgemen
t between the elect and the damned, the exact basis of the division depends on whether it is God’s will, religious faith, or good works that is supposed to be the decisive criterion. Even those who emphasize the inscrutability of the divine will for each soul, or the importance of faith over works, would generally hold that God’s chosen ones will be righteous in this life, even if that righteousness is not itself the reason for their salvation. The important point is that religious belief in a future life has always been intimately connected with the ethical and social question of how to live in this one.
Brain and mind
That the brain is the organ of the mind has become increasingly apparent through modern scientific research. This discovery has led some to question traditional beliefs about the existence of an immortal soul and the possibility of an afterlife.
Nineteenth-century attempts to specify the exact nature of the connection between brain and mind included the science of ‘craniology’ or ‘phrenology’, according to which the extent of the development of different sections of the brain could be discerned from the shape of someone’s skull. The different parts of the brain under the ‘bumps’ on the skull were correlated with different mental traits, such as love of children, secretiveness, self-esteem, and so on. Phrenologists could thus tell people what the shape of their head revealed about their mental capacities. It became a popular craze for a while in Victorian Britain and functioned as a sort of neurological version of reading one’s horoscope. People were fascinated to be told about what their bumps revealed about their character traits and their future destinies, by those with a special understanding of the secret workings of nature. Queen Victoria even arranged for her children to be given phrenological readings.
