- Research article
- Open Access
Argumentation and fallacies in creationist writings against evolutionary theory
Evolution: Education and Outreachvolume 7, Article number: 11 (2014)
The creationist–evolutionist conflict is perhaps the most significant example of a debate about a well-supported scientific theory not readily accepted by the public.
We analyzed creationist texts according to type (young earth creationism, old earth creationism or intelligent design) and context (with or without discussion of “scientific” data).
The analysis revealed numerous fallacies including the direct ad hominem—portraying evolutionists as racists, unreliable or gullible—and the indirect ad hominem, where evolutionists are accused of breaking the rules of debate that they themselves have dictated. Poisoning the well fallacy stated that evolutionists would not consider supernatural explanations in any situation due to their pre-existing refusal of theism. Appeals to consequences and guilt by association linked evolutionary theory to atrocities, and slippery slopes to abortion, euthanasia and genocide. False dilemmas, hasty generalizations and straw man fallacies were also common. The prevalence of these fallacies was equal in young earth creationism and intelligent design/old earth creationism. The direct and indirect ad hominem were also prevalent in pro-evolutionary texts.
While the fallacious arguments are irrelevant when discussing evolutionary theory from the scientific point of view, they can be effective for the reception of creationist claims, especially if the audience has biases. Thus, the recognition of these fallacies and their dismissal as irrelevant should be accompanied by attempts to avoid counter-fallacies and by the recognition of the context, in which the fallacies are presented.
The antagonism between religion and natural sciences is often a reflection of perceived contradictions between scientific data and (personal) interpretation of religious texts, especially the Bible (McGrath ). The acceptance of biological evolution by the public varies being the highest in Iceland (84.9%) and Denmark (82.2%) and the lowest, e.g., in the United States (39.7%) and Turkey (26.0%) (Data360.org ; 34 countries sampled). The theory of evolution since Wallace () and Darwin () suggests that humans developed naturally over a very long period of time from other life forms. This is a challenge for some forms of religious faith that perceive humans separate from other organisms and emphasize the literal interpretation of the Bible (Numbers , McGrath ).
Traditionally, creationism has been classified into four principal types (Scott , McGrath ). Young earth creationism (YEC) states that the earth was created 6000–8000 years ago and the flood of Noah occurred exactly as written in the Old Testament. Old earth creationism (OEC) interprets the six-day creation story symbolically to represent longer time periods to accommodate the geological age of the earth. Intelligent design (ID) requires supernatural intervention during the formation of basic body plans and biological molecules by trying to identify “irreducible complexity”, i.e., structures that could not have evolved by natural processes only. Theistic evolution accepts biological evolution as a tool of a deity to produce the observed biodiversity (McGrath ) and, thus, it is “creationism” only in the broadest sense.
YEC, OEC and ID mostly share a common notion of “individually created kinds” (Hebrew מִין [min], “kind”; e.g., Genesis 1:11–25, 6:19–20; King James Bible ). Creationists (especially YEC) consider variation and change possible within the “kinds”; however, any change of a “kind” into another or the appearance of new “kinds” requires supernatural intervention (ID). While there is disagreement on the classification of “kinds”, YEC, OEC and ID state that the evolutionary concept of these taxa developing as a result of natural processes is false (McGrath ). The creationist “kind” is not the same as the taxonomical species but corresponds often closely to biological families (Numbers ).
Creationist writings attempt to disprove biological evolution (YEC, OEC and ID) and the age of the earth (YEC) by various strategies. One approach is to present selected data from natural sciences as counter-evidence against evolution, which has produced also numerous rebuttals from evolutionary proponents (Young , Shermer , Pennock , Isaak , Deming , Durrett and Schmidt , Panda’s Thumb ). These scientific rebuttals are not discussed in detail here. Creationist writings present also repeated arguments that are not directly connected to the scientific proof of evolution. We used argumentation-oriented textual analysis to unravel prevalent practices that dominate the creationist–evolutionist debate. We hypothesized that discursive practices not based on debating observational evidence per se would contain fallacious arguments that could eventually affect the reception of the creationist claims by their audience.
Creationist authors and publications were chosen for analysis based on their visibility and impact in social media (Table 1). To assess the potential significance of these English-language-derived creationist arguments locally, highly-cited Finnish creationist authors were also analyzed. We included a sample of rebuttals by evolutionary proponents to analyze if similar fallacies could be observed on both sides of the debate. The analysis proceeded as follows: we determined the position of the writer in the creationism–evolution conflict (pro-creationism, anti-creationism). The creationist texts were classified as YEC, OEC or ID, but there was a lot of overlap between OEC and ID, which is indicated by ID/OEC. We excluded theistic evolution, as it basically accepts biological evolution (International Theological Commission ). The arguments were analyzed and classified according to argumentation theory with methods employed previously (Sahlane ). We also inspected the arguments according to the context of proving or disproving theories within natural sciences, i.e., we documented if the texts, books, journal issues or Internet sites that contained fallacious arguments also discussed the “scientific evidence” for creationism.
The relevance of the arguments as proof for or against evolution was based on the methodology of biological research. Very briefly, the process includes i) observations (such as the fossil record) and experimental data (e.g., DNA sequences). ii) The data are analyzed and interpreted based on existing knowledge and finally iii) the hypotheses are tested, auxiliary hypotheses, negative and zero findings considered and the manuscript is submitted to review, iv) scrutinized and rejected or published. The method also v) requires the data to be reproducible. Thus, evidence and not, e.g., personal characteristics of scientists, determines the validity of a theory. We assessed the fallacies against this background and discussed the findings with alternative hypotheses, i.e., if there are cases where the arguments would be valid and not fallacious in the context of disproving/proving evolution.
Fallacies are “violations of rules for critical discussion” that undermine the efforts to reach a rational outcome of a controversial issue (van Eemeren and Grootendorst ). Fogelin and Duggan () argue further that fallacies are not simply “invalid argumentation”. They can also be regarded as “…a general term for criticizing any general procedure used for the fixation of beliefs that has an unacceptably high tendency to generate false or unfounded beliefs”. The present study does not aim to assess if the claims presented by creationists are “true” or “false” but evaluates if some of the repeating arguments used to validate creationism are improper in scientific context and can be disregarded as proofs against evolution. Fallacies were classified according to the scheme in Table 2.
To assess the prevalence of the analyzed fallacies in the sample material, the presence of a particular fallacy in a single article, book or online text was listed. However, the TalkOrigins archive’s general homepage was excluded as it is mostly an index and does not contain text per se. Multiple occurrences were not recorded due to the vast differences in text length. The distribution of the fallacies between YEC, ID/OEC and pro-evolutionary texts was analyzed with the χ2-test or, in case the test criteria were not met, with the Fisher’s exact test (SPSS v 19 software package, IBM, Armonk, NY, USA). The results are presented as percentage of texts within category (YEC, ID/OEC or pro-evolutionary) that contained the fallacy. The p value <0.05 was considered statistically significant.
Ad hominem fallacies
The direct ad hominem attempts to disqualify the opponent’s legitimacy in the issue (van Eemeren and Grootendorst , Sahlane ). In creationist writings, ad hominem fallacies display Darwin as racist, sadist, psychotic and dishonest (Bergman [2004, 2005], Brace [2004, 2006]; Table 3). There are also ex silentio arguments accusing him indirectly of racism and genocide: “(He) failed to condemn the destruction of primitive races” (Puolimatka ). An oft-repeated argument concerns Haeckel, who is considered a racist and criticized for forgery in his embryological drawings (Reinikainen , Luskin , Puolimatka [2009, 2010]). More recent proponents of evolutionary theory can be referred to as “the premier atheistic populist propagandist for evolution” (Brace ) or as “a Marxist atheist” (Reinikainen ).
Another form of direct ad hominem suspects the evolutionists’ qualifications or integrity (Table 3) by stating, for instance, that “Darwin himself was not a scientist… he was a one-time preacher of the gospel who went astray…” and “Darwin heavily plagiarized his theory… and many believe that he seized upon a chance to acquire fame and security at least partially from the work of others” (Brace ). Direct ad hominem occurs also when scientists, whose words have been previously cited as supporting creationism, have published more recent texts taking the opposite view. For example, there is the well-known statement by Popper on the concept of natural selection not being scientific (Johnson , Puolimatka ), which he later reformulated (Popper ). The change of opinion is attacked by stating that “[Popper] was besieged by indignant Darwinist protests” (Johnson , Puolimatka ). Likewise, there is a creationist report citing a scientific paper about the alleged discovery of “dinosaur blood” (Wieland ). When an author of the original report (Schweitzer et al. ) refuted the YEC claim, she was criticized for “being under a lot of pressure and, of course, has tried to wriggle out of these observations… to preserve her credibility in the scientific community” (Reinikainen ).
In the sampled creationist writings, the indirect ad hominem (tu quoque) occurs most often in two forms (Table 3). The first type accuses evolutionary proponents of using arguments that they themselves condemn when used by creationists. Typically, creationists criticize evolutionists of introducing religious arguments while demanding that religion should not be allowed to enter scientific discussions (Johnson , Puolimatka ). The second type deals with quotes of evolutionary proponents allegedly affirming, for instance, that the fossil record would be seriously deficient. These citations can also be considered quote mining, out-of-context citations used to promote an argument (Young , Pieret ). Opinions of scientists can obviously be based on research but proof does not depend on the person but only on the actual evidence itself. In the above cases, the arguments also approach the two wrongs make a right fallacy, where a potentially wrong action (introducing religion into natural sciences by a creationist) is defended by pointing to similar actions by those of the opposite opinion.
In creationist texts, the poisoning the well fallacy often takes the form of indicating evolutionary proponents as having too strong naturalistic biases, which prevent them from considering supernatural hypotheses (Harris and Calvert ). This is clearly formulated by Puolimatka (): “When discussing with dogmatic naturalists it can be futile to raise the question about the truth of evolutionary theory, because from their religious [naturalism taken as religion] viewpoint this question cannot be even posed in a meaningful manner” and “The atheist or agnostic approaches are the only alternatives accepted in the discussion”.
Appeals to authority
Appeals to authority are fallacies, where the claim is presented as right because an expert or an authoritative power says it is right (van Eemeren and Grootendorst ). In the sample material, the authoritativity of the authors referred to is often augmented by including their merits and (religious) affiliations when cited. For example, criticism for naturalistic abiogenesis is accompanied by stating that an influential critic of the theory (“cells cannot be born out of inorganic substance in reality or in theory”) is “an atheistic Nobel-prize winner” (Reinikainen ). Thus, it is implicated that even atheists agree with creationists. Historically authoritative figures of natural sciences (e.g., Newton, Maxwell, Linné) are also introduced to give testimonials of their Christian faith (Reinikainen , Puolimatka ). Appeals to authorities can also occur as out-of-context citations of scientists allegedly stating that there would be serious flaws with evolutionary theory (ibid.). Also influential “converts into theism” are presented, for example, the “former atheist” Antony Flew who converted “to theism” (in reality, into some kind of deism; Carrier ) after having encountered alleged problems in evolutionary theory (Reinikainen ).
Creationists often appeal to numerous unknown authorities who oppose evolutionary theory. This takes the form of “large and/or growing numbers of scientists who doubt or renounce evolutionary theory” (Morris , Davis and Kenyon , Luskin and Gage , Puolimatka , Reinikainen ). These are also ad populum fallacies, where “the claim is supposed to be right because everybody thinks it is right” (van Eemeren and Grootendorst ). In these cases, the proportion of a population, e.g., U.S. citizens, that believes in special creation or divine guidance of evolution (82–87%) is introduced when justifying teaching ID to pupils (Harris and Calvert ). Obviously, the validity of a theory does not depend on the number of its followers.
Appeals to consequences, guilt by association, slippery slopes and straw men
Appeals to consequences typically link evolutionary theory to renouncement of theism, which would inevitably lead to immorality (Morris ) thus denying moral autonomy (Mackie , Brink ; Table 4). For instance, creationists can claim that naturalist Darwinism “provides a viewpoint, which takes the mass destruction of living creatures as a positive endpoint” (Puolimatka ). Guilt by association fallacy links the opposing viewpoint to phenomena or groups deemed unreliable or evil without concentrating on the actual evidence (Curtis ). Numerous examples link evolutionary theory to the Holocaust or other historical events. Creationists (Johnson , Puolimatka , Grigg ) also associate the acceptance of evolutionary theory to the screening of fetal disorders and mistreatment of disabled people. Examples also include connecting evolutionary theory to mass murders in welfare states (Hodge , Puolimatka , Bergman ).
Brace (), Puolimatka () and Bergman () have also claimed that the general acceptance of evolutionary theory would initiate a chain of events “going from bad to worse” including eugenics, discrimination and violation of human rights, forced sterilization and genocide. This is the slippery slope fallacy (van Eemeren and Grootendorst ; Table 5). For the slippery slope argument not to be fallacious, the disclaimer should be able to present logical causal relationships between the consecutive steps to the outcome. However, in the case of disproving evolutionary theory, this would not be sufficient, as the validity of a theory in the natural sciences is determined by evidence and not by its alleged applications. Even when the creationist writers do not directly claim that the slippery slope (or ad consequentiam) arguments disprove evolution, the association is present and, as hypothesized by Yap (), these arguments can be very effective for those observing the evolution–creationism debate.
Creationist straw man fallacies commonly deal with simplifications of evolutionary theory, such as overemphasis on random mutations or misunderstanding transitory forms, molecular differences between taxa and the origin of the universe (“…according to evolutionists a hydrogen atom formed by the Big Bang created the whole universe and life”; Reinikainen ). We do not discuss these fallacies in detail here as they have been refuted on numerous occasions (e.g., Young , Isaak ).
False dilemma and hasty generalization
In creationist texts it is usual to assume that there are only two choices: “There are only two alternatives: either the world receives its order from an outside source or the order is innate without any order given from the outside” (Leisola ; Table 6). This false dilemma appears also when considering unresolved issues in evolution or abiogenesis (“The RNA world did not resolve this problem. Thus, only creation is left as an option”; Reinikainen ) or when discussing the potential moral dimensions of evolutionary theory. Obviously, the RNA world is not the only possible explanation to abiogenesis (e.g., Gilbert , TalkOrigins archive [2013a]) and there are several rational arguments presented for the autonomy of morality (Brink ).
Hasty generalization involves making conclusions that are based on limited sources or evidence (Walton [1999a]). Creationists can claim that a single piece of data would be sufficient to disprove the whole theory of evolution. Reinikainen ([2013a]) writes that “this finding [‘unfossilized’ Tyrannosaurus rex bone] is a deathly blow to evolutionary theory”. Hasty generalization is also present when extrapolating the results of one study after creationist re-interpretation. For example, Carter () cites Hughes et al. (), who state that the difference between selected human and chimpanzee Y chromosome DNA sequences is 30%. Creationists generalize this to be the case also in other parts of the genome. Carter () continues: “…we now know that the old ‘humans and chimps are 99% identical’ canard is passé”, although the writers of the original paper make note of the fact that the other parts of the genome show 98% similarity. There are also instances of generalization, when alleged isolated problems with evolutionary theory or related disciplines are considered adequate to disprove the theory in its entirety. An example of this is the creationist approach to radiometric dating: any alleged inaccuracy is seen as a refutation of the whole radiodating method (Swenson ), while geologists point to the overwhelming amount of evidence based on various radiometric procedures and their comparison to other methods indicating to the ancient age of the earth (Wiens ).
Other creationist fallacies
Utilizing the appeal to ignorance, creationists refer to unresolved questions as proofs of fatal weaknesses in evolutionary theory or as indications that the theory is about to collapse (Morris , Johnson , Reinikainen , Behe , Puolimatka , Reinikainen ). For instance, Behe () claims that there would be “a total lack of serious Darwinian explanations” regarding cilia. A form of the argument from ignorance is the argument from incredulity (Dawkins ), in which an author simply states that a theory is inconceivable or irrational. In the sample material, there are frequent appearances of this fallacy (e.g., Morris ). Some examples are as follows: “There is not even one reasonable suggestion on how life could have emerged from inorganic matter” and “…it is hard to imagine that chance and natural selection could explain the emergence of these types of systems” (Puolimatka ).
Sometimes the supposed lack of evidence becomes a statement with no references in a repeated ad nauseam pattern, e.g., when discussing the alleged lack of transitional fossils in the form of “no transitional forms have been found in the fossil record” (Puolimatka ). The same appears in Yahya (), who states repeatedly (16 occasions) based on similarities between fossils and modern species that living beings “did not evolve, but were created”. Many of the claims presented and refuted in the early 1970’s are also continuously repeated (often without citations) ad nauseam in later creationist texts. For instance, the arguments connecting Darwinism to atrocities have re-appeared for decades (Morris , Bergman , Brace [2004, 2006], Puolimatka , Reinikainen ).
Equivocation misuses words in a manner that creates ambiguousness (van Eemeren and Grootendorst ). In the sample material, it is common to link “social Darwinism” to evolutionary theory (Bergman , Puolimatka , Bergman ). Another example is the use of the word “selfish” in the concept “selfish gene” (Dawkins [1989a]). While creationist authors may acknowledge that evolutionists do not necessarily use the word “selfish” in its everyday meaning, they still claim that evolutionists are saying that genes are “ruthlessly immoral” and that genes “created us, our bodies and our minds” and add an ad ridiculum comment: “a collection of chemicals would hardly be experiencing any vain self-satisfaction from merely being able to copy themselves” (Puolimatka ). In addition to direct equivocations, there are also conceptual equivocations: creationists interpret concepts differently from scientists. Boudry et al. ([2010b]) have pointed to equivocation in the concept “information” in ID, with its scientific interpretation of “a measure of randomness” being replaced by its colloquial use of “meaningful message” thus making it more persuasive to refer to DNA sequences as “designed”.
We present here two other conceptual equivocations in the sampled texts. The first one deals with the confusion of transitional forms and fossils. It occurs when creationists present genetic comparisons as evidence against evolution. They acknowledge that the differences in percentage between the DNA sequences of different life forms compared to humans form a sequence, in which mammals are the most similar followed by reptiles, amphibians, fish, various invertebrates, fungi, plants and prokaryotes. However, when creationists subsequently compare the sequences to prokaryotes, they notice that all the other life forms differ from bacteria by the same percentage. They surmise this to be counter-evidence against evolution (Reinikainen , Johnson , Davis and Kenyon ). Creationists claim that, as amphibians are supposedly half-way between bacteria and humans, their genes should also be more similar to bacteria than those of humans. Here the concepts of transitional forms and ancestors are confused with the descendants of these ancestors. Actually, comparisons from the human point of view reflect the time that has passed since our common ancestor with the above-mentioned life-forms lived. Thus, our last common ancestor with other mammals is more recent than that of mammals and fish (Purves et al. ), as observed in the sequences. But from the point of view of bacteria, the last common ancestor with humans, fish, invertebrates and plants is the same and all these other forms have had exactly the same time to develop since these taxa branched off from that of prokaryotes. Thus, creationists equivocate, e.g., ancestral amphibians with modern amphibians and ancestral transitional forms with the inexistent “modern transitional forms”.
The second case of conceptual equivocation appears when creationists discuss statements of evolutionary biologists that are outside the scope of actual science. For instance, they can interpret an opinion or a popularized rebuttal of an evolutionist as evolutionary science per se and utilize these texts as evidence for evolution being the only allowed doctrine in the scientific community. An example is the appeal to a biologist “S.C. Todd”, who refuted any possibility of considering supernatural explanations in the “scientific paper Nature” (“Even if all the data point to an intelligent designer, such a hypothesis is excluded from science because it is not naturalistic”, cited by, e.g., Morris  and Puolimatka , see the actual text in Todd ). The original text was published as “Correspondence” and not as a peer-reviewed scientific paper.
The no true Scotsman fallacy (Dowden ) occurs as a device to redirect accusations from creationists when the discussion has reached a state of repeated tu quoque arguments, such as in a debate on the “Darwinist” or “Christian” roots of Nazism. Creationists eliminate any possibility of them taking part in atrocities by stating that in case religious people are involved in violence, they are not “true” Christians. “We have often demonstrated that the occasional atrocities committed by professing Christians were completely contrary to the teachings of Christ, while the atrocities of 20th century Nazis and Communists were totally consistent with evolutionary teaching (original emphasis)” (Sarfati ). In the same way, a scientist refuted the use of her findings to promote YEC and identified herself as “an evangelical Christian”. This has been denounced by stating that she would not be a “true” evangelical: “[The scientist’s] attitude to Scripture actually reflects a liberal, rather than evangelical approach to the Bible” (Catchpoole and Sarfati ).
Appeal to fear or force (ad baculum) threatens the other party with sanctions (van Eemeren and Grootendorst , Woods ). Direct threats are relatively rare in the sample material, but the above-mentioned association of evolutionary theory to atrocities can also be seen as an appeal to fear. While the sampled texts do not directly threaten those who accept evolution with supernatural punishment, the authors associate the loss of faith in the literal interpretation of Biblical creation and its substitution with evolution with damnation. “There is a clear connection between creation and… the resurrection of the believers” (Reinikainen ). Ad baculum appears also when discussing the alleged fate of creationist or theistic scientists, if they publish material against evolution. “Those believing in creation are forced to silence in fear of losing their jobs or positions” (Reinikainen ). There are repeated anecdotal stories of mistreated creationist scientists unable to publish or forced to resign because of their opinions (Harris and Calvert , Puolimatka [2009, 2010]). These instances could also be classified as appeals to pity (ad misericordiam). The validity of the examples could, of course, be verified or disproved and there could exist a bias among scientists to prevent YEC and ID/OEC from being published. In the context of evolutionary science, these stories are basically irrelevant, but in the context of potential pre-existing biases in the creationist–evolutionist debate, these arguments would not necessarily be fallacious.
Fallacies in pro-evolutionary texts
Direct ad hominem attacks by evolutionary proponents on creationists are quite similar to the fallacious arguments of creationists (Table 7). Perhaps the most notorious one states that “It is absolutely safe to say that if you meet somebody who claims not to believe in evolution, that person is ignorant, stupid or insane…” (Dawkins [1989b]). Furthermore, evolutionists have stated in response to accusations of Darwin’s racism that “Price, who is to young-earth creationism what Darwin is to evolution, was much more racist than Darwin” (TalkOrigins archive [2013b]). Other personal attacks include characterization, such as “deplorable deceiver” (Buchanan ) or “Their lack of integrity may well drive any educated person away from consideration of the truth-claims of Jesus Christ” (Buchanan ).
In the sample material, evolutionists usually present the ad hominem arguments in the context of defending evolutionary figures from demonization and they could also be classified as tu quoque (Table 7). In fact, claims of evolutionary racism or Nazism are often rebutted by pointing to similar cases by creationists as follows: “The Bible Belt in the southern United States fought hardest to maintain slavery”, “Henry Morris… has in the past read racism into his interpretation of the Bible” (TalkOrigins archive [2013b]). When creationists claim that “scientists find what they expect to find”, the naturalistic rebuttal ends with the tu quoque “creationists find what they want to find” (TalkOrigins archive [2013f]). Evolutionary proponents also utilize appeals to consequences. It has been said that humankind is on the brink for “either a marvelous future, or disaster. Ignorance [creationism] will almost certainly lead to the latter” (Young ). This is also an example of a false dilemma (“marvelous future–disaster”). However, fallacies are sometimes recognized in evolutionary rebuttals. For instance, the irrelevancy of ad hominem or ad consequentiam is indicated when discussing potential evolutionary racism by stating “None of this matters to the science of evolution” (TalkOrigins archive [2013b]).
Detailed refutations to creationist claims that are out of scientific context and thus fallacious could be treated as counter-fallacies. The first type is the rebuttal of a fallacy with a response that contains the same fallacy as the original claim (very often leading to tu quoque). This seems to cause a vicious circle of fallacies and counter-fallacies that can eventually dominate the discussion. The other type of counter-fallacy is the ignoratio elenchi or irrelevant argumentation fallacy (van Eemeren and Grootendorst ). In this case, the opponent produces a detailed and carefully formulated response to a fallacious argument, such as the association of evolutionary theory to Nazism. The response (e.g., TalkOrigins archive [2013c]) includes cited examples of the Nazi party being opposed to evolutionary theory, Hitler’s Christian background and a well-balanced conclusion that “of course, this does not mean that Hitler’s ideas were based on creationism any more than they were based on evolution. Hitler’s ideas were a perversion of both religion and biology.” It can certainly be useful to discuss and unravel the motivations and historical background of Nazism but, at this point, the debate has left the context of evolutionary evidence and the original fallacious ad consequentiam argument is treated as if it were relevant to the discussion of evolutionary proof.
Prevalence of fallacies
All above-mentioned fallacies were present in the sampled texts with the highest prevalence being 100% for tu quoque in ID/OEC, 88% for appeals to authority in YEC and 56% for ad hominem and tu quoque in pro-evolutionary texts (Figure 1). The prevalence of direct ad hominem did not differ between the classifications (YEC, ID/OEC or pro-evolutionary); regarding most of the other fallacies, the prevalence was lower in pro-evolutionary texts. The prevalence of ad ridiculum was higher in ID/OEC compared to the other text types.
Discussion and conclusions
The creationist–evolutionist discussion focuses on scientific dispute on the evidence regarding evolutionary theory but, in reality, creationist texts contain numerous fallacious arguments not directly if at all related to the issue of science. A large part of scientific rebuttals concentrates on these fallacious claims and eventually leads to counter-fallacies. Ad hominem and tu quoque arguments were especially prevalent in all forms of creationist and pro-evolutionary texts. However, it must be emphasized that the analyzed texts were not selected randomly but based on visibility and impact. Thus, the results on the prevalence of fallacies in the creationist–evolutionist debate do not necessarily reflect a general pattern. Still, we can tentatively surmise that most of the examined types of fallacies commonly occur in the analyzed forms of creationism. Creationist claims are often based on criticizing evolutionary theory by using selected data derived from scientists. In addition, also opinions and popularized books of evolutionary proponents are equivocated to represent the actual evolutionary theory. The use of these, often out-of-context pieces of data, leads to rebuttals and it is often these refutations that contain the counter-fallacies of evolutionary proponents. Still, participation in the debate in a rational manner would require both parties to avoid irrelevant fallacies whenever possible.
Furthermore, creationist fallacies are international. The sampled Finnish texts consisted largely of paraphrases and translated citations of English-language creationist texts and used the same tu quoque quotes (often out of context) as international creationist sites (Puolimatka [2009, 2010]; Table 3). The general pattern of creationist “scientific evidence” is to select and re-interpret a piece of data from main-stream science and publish it in a creationist journal with a reference to the actual study (Carter ). In the Finnish texts, the only remaining reference is often to the creationist paraphrasing, which is presented as the “proof”, for instance in the above-mentioned debate on the alleged human–chimpanzee genetic difference of 30% (e.g., Reinikainen ).
Within the context of the present study, the observed fallacies are not relevant when considering scientific evidence against evolution. Still, for instance, in legal settings ad hominem (or guilt by association) could be a valid argument when using character witnesses to assess the reliability of a defendant (Yap ). In fact, creationists have employed this strategy by using the narrative of evolutionary theory or “Darwinism” as the accused party and presenting unpleasant moral associations between (proponents of) evolution and various atrocities. Johnson () uses this by discussing evolutionary theory almost as a case to be judged in a legal court. Johnson states that his aim was “to examine the scientific evidence on its own terms, being careful to distinguish the evidence itself from any religious or philosophical bias…” However, in the same work he utilizes appeals to authority, tu quoque and ad consequentiam with references to Stalinism, Marxism and Nazism. While these arguments can be relevant in court (Yap ), this strategy is fallacious in evolutionary debate, because the credibility of the scientist is ultimately quite irrelevant: the claim can always be confirmed by the original data and/or repeating the experiments. Still, it must be acknowledged that it is virtually impossible to employ source criticism on all occasions and some data may have to be considered reliable after peer-review without examining the original evidence. Discussion about the integrity of scientists can certainly be useful and not fallacious in the context of reliability even if it did not provide actual proof on a theory.
The examples of ad hominem and ad consequentiam as well as the appeals to authority (such as court cases) in pro-evolutionary writings should also be scrutinized regarding their context. It can be argued that these examples would not be fallacious if their aim was to draw the attention of the audience to possible lack of expertise and not only to reject the opposing viewpoint. In a similar manner, the ad consequentiam stating that creationism leads to disruption of scientific research (e.g., Young ) would not necessarily be fallacious in the context of discussion about society and education. However, to avoid counter-fallacies, it would be prudent to express clearly the actual aim stating, for instance, that the argument is not about the scientific evidence for or against creationism (which would be discussed elsewhere) but about the implications (educational, theological, sociological, etc.) creationism would have if it were adopted as the theory on the appearance of life and biodiversity on the earth. The theological arguments of evolutionary proponents and the dismissal of these by the tu quoque arguments of creationists also merit further consideration. It may seem plausible that evolutionists themselves use a fallacy when introducing religion in evolutionary debate. However, in these cases, evolutionary proponents refer to the potential theological implications of creationism, i.e., what the characteristics of a deity or an intelligent designer would be, if YEC or ID were true. For instance, Dawkins () discussed the skull form of the flounder as something which would be hard to explain if ID was correct and the form had been designed by a supernatural entity. In the context of an omnipotent, omniscient and perfectly good God, the arguments of imperfection and suffering are quite legitimate as argued also by Boudry and Leuridan (). Thus, the creationist tu quoque remains a fallacy, as evolutionary biologists have the right to participate in the discourse over ID. Of course, the validity and rationality of their theological claims can be assessed within that frame.
An explanation to the creationist hasty rejection of a method or theory based on a small number of divergent data can perhaps be found in the (YEC) paradigm of literal interpretation of the Bible. In the context of argumentation theory, one proven error in a text would not automatically mean that any other part of the same text would be erroneous. Thus, one error in the Bible would not automatically undermine any other part of it. However, for YEC, one error in the Bible would mean that the certainty of all the other parts would be jeopardized: it would be impossible to abandon the historicity and divine authority of the Genesis without a collapse in the authority of the whole Bible (Reinikainen [1991, 2011]). The same approach seems to be used when creationist writings criticize evidence for evolution: alleged isolated inaccuracies can be taken as detrimental for a whole theory or method (e.g., radiometric dating, Swenson ). Yet, in the disciplines of natural sciences, there never was any certainty to begin with. The theories are based on (statistical) interpretation of evidence and not taken as literal truths. The transfer of the paradigm of personal belief or YEC/ID/OEC dogma with the requirement of inerrancy to natural sciences where the possibility of errors is always present yields fallacious arguments that do not strengthen the creationist case.
Fallacious argumentation is not irrelevant in the context it is presented in. In fact, the vicious circle of fallacies and counter-fallacies can make the science seem irrelevant and the character of the scientists, their opponents and the real or imagined moral implications of science the most relevant part of the discussion. The decades-long debate with the same fallacies being constantly repeated ad nauseam could be an indication of this. When presented in a context of “scientific creationism” (i.e., modern YEC) or ID/OEC, the observed fallacies could be effective tools to persuade an audience (Yap ). We tentatively divide the potential audience into three groups as follows: i) those with existing creationist convictions or biases, ii) the undecided and iii) those with pro-evolutionary convictions or biases. The first group could react as suggested by Yap (), where the audience with pre-existing biases evaluates the arguments based on fallacies. This can “fix beliefs” or “generate false or unfounded beliefs” (Fogelin and Duggan ). In fact, it has been suggested that the appeal and persistence of the creationists’ ideas do not depend on the “science content” of YEC or ID/OEC but on their cultural, sociological and cognitive dispositions (Boudry et al. [2010a]). There could also be a connection between religiosity and the effects of these biases (Blancke et al. ), especially when considering that creationism is based on the literal interpretation of the Bible.
In the case of an evolutionary proponent, the reaction to repeated fallacies could be that of irritation (possibly subconscious if the fallacy and its context are not recognized) and lead to counter-fallacies as presented above. Examples of the latter reaction are available in pro-evolutionary Internet sites that can include the recognition of fallacies but, at the same time, the rebuttals of fallacious claims also include tu quoque (e.g., EvoWiki ) and disqualification of creationists as opponents (Pigliucci et al. ). This strategy has apparently not been able to reduce the widespread utilization of scientifically irrelevant fallacies in creationist (or evolutionist) texts, and also previous reports have suggested that natural scientists should concentrate on discussing ID claims based on purely evidential grounds (Boudry et al. [2010b, 2012]). Our results strengthen the notion that the constant use of fallacies in persuasion can be a factor in the continuing success of creationism despite of scientific counter-evidence. Based on the present analysis, we present here an alternative way to approach the fallacies in creationism.
Discuss the scientific claims with arguments that are valid for natural sciences.
Recognize fallacies and determine if the fallacious arguments are relevant for the science content.
If the fallacies are irrelevant for science, analyze the context of the fallacy within the book, journal article or Internet site. Is the science content presented together with fallacies? Discuss the fallacy as a potential tool for creating erroneous beliefs for the audience.
Avoid counter-fallacies, especially ad hominem in your rebuttal. If you feel it is necessary to refute ad hominem and ad consequentiam claims with a detailed counter-fallacy, acknowledge the irrelevance of the issue in the scientific validity of evolution. If the argument is relevant and not fallacious regarding, e.g., education and social issue, acknowledge this. Remember the fallacist’s fallacy (Curtis ): a claim is not wrong simply because it is defended by a fallacious argument.
When discussing the theological implications of, for example, ID, remember to clarify that the context is not evolutionary theory but the potential absence of it, i.e., creationism.
While the suggested approach is tentative, it should not cause anxiety in either party of the creationist–evolutionist debate. Obviously, the scientific rebuttals against YEC and ID/OEC claims would remain detailed and well-formulated even without the concomitant counter-fallacies. The same would ultimately benefit creationists if their goal is to let the evidence decide and let the theory that explains best the biodiversity of the natural world prevail.
Old earth creationism:
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The authors sincerely thank Dr. Maarten Boudry, Doc. Esko Ryökäs and MA Ulla Nieminen for their critical comments on the manuscript.
The authors declare that they have no competing interests.
PN designed the study, collected the sample material and conducted the textual analyses. AMM commented on the analyses. PN wrote the first draft of the text and the final form was accomplished by both authors. Both authors read and approved the final manuscript.
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