In order to answer this question, we need to think a bit more deeply about what it is that divides genuine science from fake science (pseudo-science). There is a volu- minous literature in the philosophy of science on just this topic, but for our pur- poses we can short-circuit this huge literature to a certain extent by considering the judgement passed down by one Judge William Overton in 1982, in a famous ruling known as McLean versus the Arkansas Board of Education.
The background to the case was that it had been decreed that creationism should be taught in publicly funded schools in Arkansas alongside evolutionary theory as an alternative scientific account of our origins. The court case was brought by those unhappy with this development, who argued that creationism is not a scientific pro- posal but merely the expression of a certain religious view, and hence had no place being taught in a US publicly funded school (since the US constitution forbids the advocacy of religion in publicly funded schools). After hearing the testimony of var- ious parties, including the testimony of several influential philosophers of science, Judge Overton was called upon to give a ruling in this case. He decreed that crea- tionism wasn’t a genuine scientific proposal, and so it would not be constitutional for it to be taught in publicly funded schools. What is interesting for our purposes is that Judge Overton offered a very concise summary of the conditions which mark out genuine science (like evolutionary theory) from pseudo-science (like creation- ism). He summarised them as follows:
1 It is guided by natural law;
2 It has to be explanatory by reference to natural law;
3 It is testable against the empirical world;
4 Its conclusions are tentative (i.e. are not necessarily the final word); and 5 It is falsifiable.
All of these claims are plausible criteria for distinguishing genuine science from pseudo-science, but they are also individually contentious too. Let’s look at each of them more closely.
We will begin with the first two. ‘Natural law’ here simply refers to the laws of nature, so the first claim is saying that a scientific theory appeals to laws of nature
•
(and is consistent with those laws), and the second claim is saying that a scientific theory explains phenomena by appealing to laws of nature. Clearly, creationism doesn’t satisfy either of these criteria since a key part of the view is an appeal to explicitly supernatural events, such as divine intervention in the world. Moreover, creationism is quite open about explaining phenomena by appealing to such super- natural events. Evolutionary theory, on the other hand, does not appeal to anything supernatural (i.e. it does not appeal to anything outside the natural law).
Next, consider points 3 and 5. To say that a theory is testable against an empirical world means that one can find evidence in nature which would count in its favour, and also evidence which, even by the lights of the proponents of the view, could count against it (i.e. counter-evidence). It’s pretty clear what could constitute evi- dence in favour of evolutionary theory, such as finding new fossils that confirm a hypothesis of evolutionary theory as yet unconfirmed by the fossil record. It’s also pretty clear what could count as counter-evidence against evolutionary theory. If, for example, we discovered something in nature which did seem to be irreducibly complex in the way that some creationists allege, then this would be very strong evidence against evolutionary theory.
But what would count as evidence for, or counter-evidence against, creationism? To focus our minds, let us attend specifically to the question of what could count as counter-evidence against this view. Given that evolutionary theory and creationism are incompatible views, the obvious place to start here is with the evidence for evo- lutionary theory, since this will tend to be counter-evidence against creationism. So, for example, consider the fossil record, which appears to suggest that the world has existed for a very long time. Creationism explains this putative counter-evidence away by appealing to a supernatural explanation (i.e. that God created the world replete with the traces of a distant ancestry, such as a fossil record). The trouble is that any putative evidence one would care to list against creationism can easily be explained away by the same technique. Thus, creationism doesn’t appear to be empirically testable at all.
The demand made in claim 5 (i.e. that a scientific theory must be falsifiable) is stronger than that in claim 3, but of the same sort. (Note that we have met falsi- fication before, in Chapter 10, where it was presented as part of a view known as falsificationism, which purported to offer a way out of the problem of induction.
But for our current purposes try to set this to one side and consider condition 5 in its own right. We will critique this condition in due course.) To say that a scientific theory must be falsifiable means not just that there could potentially be empirical evidence which counts against it, but also that there could be empirical evidence which decisively shows that the view must be wrong. Finding something in nature which seems irreducibly complex in the way described above would be counter- evidence against evolutionary theory, but given the tremendous success of the view, one would hardly think that this should suffice to reject the view out of hand. Per- haps the view just needs to be adapted in some peripheral way to account for this newly discovered phenomenon, or perhaps on closer inspection this phenomenon is not what it appears and so doesn’t present the challenge to evolutionary theory that
scientific knowledge 115 it seems to. Even so, one can certainly imagine how a wealth of counter- evidence against evolutionary theory could emerge over time to make the view simply unten- able, such that it will have been falsified. Crucially, however, since creationism is immune to empirical counter-evidence, it follows, a fortiori, that it is thereby immune to falsification too, since no body of counter-evidence could ever emerge which sufficed to falsify it.
That leaves claim 4. In a sense, claim 4 follows from claim 3. As noted above, to say that a theory is testable against the empirical world is to say that there can poten- tially be counter-evidence to this theory in nature. If that’s right, however, then any scientific proposal will inevitably be provisional, since who knows what counter- evidence might be around the corner? This is why even a well-confirmed scientific theory like evolutionary theory is nonetheless open to counter-evidence. This is not because it lacks adequate empirical support, since it enjoys a very high level of empirical support, but rather reflects the fact that even a very high level of empiri- cal support is compatible with there being as-yet-unknown counter-evidence which counts against the view, perhaps fatally so. It is in the very nature of scientific theo- rising that it be tentative in this way, in the sense that scientific inquiries are by their nature entirely open. That is, there is always scope to learn more about the world, such as by developing new technologies that widen our empirical horizons (think, for example, of how the invention of the microscope or the telescope expanded the kinds of empirical evidence available to scientists), or by developing new perspec- tives on the scientific evidence we already have (such as when one discovers that a body of scientific data has been corrupted by a hitherto undetected bias). In short, there is no such thing as the ‘final word’ in science.
Crucially, creationism is not a tentative proposal in this sense. Indeed, the people who endorse creationism endorse it precisely because it accords with their previ- ously held religious faith. Accordingly, since no matter what evidence they unearth they would retain their religious conviction (that’s what makes it faith, after all), so their commitment to creationism isn’t sensitive to future potential counter- evidence.
In this sense, at least, it is very different to the sort of provisional endorsement of a theory that is the hallmark of scientific inquiry.
We can bring this point into sharp relief by noting that there is a very different direction of fit between theory and evidence when one compares the viewpoints of creationism and evolutionary theory. Proponents of evolutionary theory endorse this view because it is the view that the scientific evidence supports (i.e. they believe the theory because of the evidence in its favour). If sufficient counter-evidence came along which counted against this proposal, then – like other scientific proposals in the past that were once widely held but which are now widely rejected – it would be ultimately replaced by an alternative scientific proposal that could accommodate the data better.
Indeed, the history of science includes a number of high-profile cases where a well-entrenched scientific theory is cast aside in favour of a competing proposal on account of its inability to deal with a growing body of counter-evidence. For example, it was once widely held that there was an element known as ‘phlogiston’ that was
contained in combustible substances and which was released during combustion.
But over time, as the counter-evidence to this theory built and built, it was realised that there simply is no such element.
In contrast to the tentative way in which scientists endorse their theories, such that they would reject theories if the counter-evidence against them became strong enough, there is nothing tentative about the creationists’ advancement of their view. Recall that proponents of creationism have already decided, on non-scientific grounds, that God created the universe, and so their endorsement of creationism is ultimately not because of the scientific evidence in its favour but because it accords with their already held religious conviction (i.e. they seek evidence in favour of the theory because it supports what they believe). For that reason, they are unlikely to alter their endorsement of creationism in response to scientific evidence, no matter how much this evidence might count against their theory. They endorse creationism not because it fits with the scientific evidence, but rather because it fits with what they already believe, and what they will continue to believe whatever scientific evi- dence comes their way.
Thus far evolutionary theory seems to have very much the upper hand over crea- tionism, with the latter looking distinctively like pseudo-science rather than genuine science. But before we definitively draw this conclusion, we should pause to con- sider some further points that are relevant here. To begin with, we should note that the epistemic sin of dogmatism (i.e. sticking to one’s view no matter what counter- evidence comes along) is not confined to creationism. Indeed, there are undoubtedly proponents of evolutionary theory who are so psychologically wedded to the view that they would no more be inclined to reject it than a creationist would be inclined to reject creationism in light of the counter-evidence. Do such people cease to be scientists on account of this fact?
Well, they certainly cease to be good scientists, since the eschewal of dogmatism is held to be an ideal of scientific endeavour, something that scientists should aspire towards. But is bad science thereby pseudo-science? This is a deep point, in that while there is clearly a difference to be drawn between bad science and pseudo- science, the distinction is far from sharp. Indeed, once we acknowledge that genuine science can be done badly, then this raises the question of why we should exclude creationism from the canon of genuine science at all. Why not instead regard it merely as genuine science done in a sub-optimal way (i.e. as bad science, rather than pseudo-science)?
We are thus faced with a three-way distinction between good science, bad science, and pseudo-science. The exemplars of normal scientific inquiry fall into the first camp, but it is unclear who falls into the other two camps. Here is one ‘test’ that we can run. While good science incorporates most if not all of the claims 1–5 listed previously, bad science falls down on at least two of these claims, and pseudo- science doesn’t satisfy any of them. This would get us a broadly satisfying result. For exam- ple, it would make bad science at least an approximation of good science, unlike pseudo-science, which isn’t even in the ballpark of being genuine science. Another
scientific knowledge 117 advantage of this proposal is that the difference between the three categories wouldn’t be at all sharp, in that it would be a matter of degree: good science shades into bad science, which ultimately shades into pseudo-science. This way of conceiv- ing of these three categories seems borne out in our normal ways of thinking about inquiry, in that there doesn’t seem to be a sharp distinction between good and bad science or between bad science and pseudo-science, even though there are intui- tively three genuine categories in play here.
Note, however, that this way of characterising the nature of scientific endeavour takes for granted that Judge Overton’s classification of science is broadly correct, and yet, as we will see in the next section, this is open to question.
The climate change debate
One of the most important scientific debates of modern times concerns climate change (i.e. global warming). What makes this scientific debate so significant is the danger that such climate change might pose, not just to particular regions of the world, but to human civilisation itself. Indeed, if climate change does pose such an existential threat, then it has profound implications for public policy, since obviously this will entail that a great deal of our resources should be redirected to offset such a calamity.
What is interesting about the climate change ‘debate’ is that in one sense, it isn’t really a debate at all, in that most of the scientists concerned are broadly in agreement both about the fact that there is climate change and that this climate change is at least in large part due to human activity. Inevitably, as with all scientific debates, one would expect there to be competing views in play about particular claims. In this debate, for example, there are arguments within the scientific community about the precise extent of the global warm- ing and, relatedly, about what is the best short- to medium-term prediction of further global warming in the future. But such local scientific disagreements belie a general scientific consensus regarding the main issues.
Of course, consensus is not the same thing as universal acceptance. In the climate change debate, as with most scientific views, there are some scientists who explore, and perhaps even advance, perspectives that are at odds with the prevailing consensus. But there is nothing inherently unusual about that;
indeed, it is just what we would expect, as every scientific consensus incorpo- rates some ‘outliers’ who don’t accept the prevailing orthodoxy.
Interestingly, however, despite this prevailing scientific consensus about climate change, the media representation of the issue often presents the scientific com- munity as being completely at odds, as if there is no consensus among climate change scientists about this topic. There are various possible reasons for this.
(continued)
(continued)
One possible explanation is that media outlets simply misunderstand that scientific debate, even when there is lots of agreement, also still involves disa- greement and also some radical ‘outlier’ proposals that challenge the prevail- ing conventional wisdom. Thus, when journalists discover any disagreement within science – even when the disagreement concerns relatively minor matters, or where the dissenter is clearly taking a minority view within the discipline – they tend to represent this as being something more dramatic than it is, as if in this particular field there is an unusually high level of disagreement.
A second possible explanation is that the demands of the media are not the same as those of science. The media have a responsibility to give both sides of a debate a fair and even hearing, even when only one of the sides to the debate is scientifically respectable. Moreover, the media are concerned with a good story, and reporting on consensus isn’t nearly as newsworthy in this regard as reporting on dissent.
A third possible explanation is that there are some actors within the public debate on climate change who simply aren’t scientists, or at least aren’t sci- entists who have expertise in the relevant fields. Dissent from these quarters looks very much like a scientific debate, and one can see why a media outlet might represent it as such (e.g. the person making the relevant editorial deci- sion to include a particular dissenting voice might not be particularly scientif- ically informed about the debate at issue). And yet when scientific expertise comes up against dissent, we surely take into account where this dissent comes from and what its epistemic credentials are. Dissent from a scientist who does not work in the relevant field is prima facie questionable in a way that dissent from a scientist who is an expert in the relevant field is not.
A final possible explanation that we will consider here (this list is not meant to be exhaustive) is that given the enormous implications for public policy in- volved in the climate change debate, it is perhaps unsurprising that the scien- tific consensus might not be taken at face value. Dealing with climate change may be expensive, and may involve significant changes to our way of life, particularly in the developed world. Won’t we be particularly suspicious of the evidence in favour of climate change given this fact? Moreover, we should also always remember that there are some powerful elements in society, such as some large multinational corporations, who may have a lot to gain by en- couraging people to think that the scientific community is more divided on the climate change issue than it is.