The Genetic Fallacy

Here is an excerpt from my book The Outsider Test for Faith. There are a lot of gems like this tucked away in that book! Enjoy!


The genetic fallacy is committed whenever it’s argued that an idea is false because of its origination or source rather than based on its merits. Even unreliable sources can produce ideas that are true. So just showing that an idea originates from an unreliable source does not necessarily make the idea false. David Marshall argues that I commit this fallacy: “If we adopt certain beliefs because we have been taught them, does that really mean they are probably false? Obviously not. The general form of Loftus’ argument is: 1) Ideas about X vary among cultures; 2) The beliefs one adopts about X originate in one’s culture, and in that sense depend on it; 3) Therefore one’s beliefs are probably wrong. This seems to commit the genetic fallacy.”

This charge of his is false. I allow that a religion could still pass the OTF even despite its unreliable origins in our respective diverse cultures, so I’m committing no fallacy by arguing correctly that those origins are demonstrably unreliable. At best there can be only one true religion in what we observe to be a sea of hundreds of false ones, which entails a very high rate of error for how believers first adopt a religion. Hence, believers need some further test to be sure their faith is the correct one. That conclusion is not fallacious, nor is the skepticism that it entails. I’m not arguing that religious faiths are necessarily false because of how believers originally adopt them. I’m merely arguing that believers should be skeptical of their culturally adopted religious faith because of it.

Acknowledging these disclaimers of mine, retired Christian professor of philosophy Mark M. Hanna let’s me off the hook on this; otherwise, he says, “the genetic fallacy charge would stick.”14 But he also alleges that my disclaimers contradict other assertions of mine in which I state that no religion can pass the OTF.15 The problem here is that Hanna has failed to distinguish between the three stages of the arguments for the OTF in this book. My disclaimers are real. It’s just that statements in which I argue that no revealed religion can pass the test represent the third stage of argumentation. The third stage, as I said, is where people can use the OTF as a basis for debates about religious faith.

Hanna claims, however, that any conclusions based on the anthropological data argued for by David Eller “fall into the genetic fallacy.” Anthropology is a merely descriptive science, Hanna argues, and so any conclusions based on it “fall outside the scientific parameters of anthropology.”16 Eller knows that anthropology is merely a descriptive science, but there is no reason why he cannot state his conclusions based on all that he knows. He is someone we ought to listen to, since anthropology is his field of expertise. He’s studied world religions, their origins, their pervasiveness, their cultural impact, and their evolution. And he concludes that if there is a correct religion, it looks indistinguishable from how the others originated, took root in a culture, and evolved down the centuries. They all look like human inventions to meet the perceived needs of the people of their times. So he says that at some point along the line “comes the epiphanal moment,” whereby, just “like the anecdote about the religion that believes the world stands on a turtle,” it dawned on him that “Christianity is cultural all the way down.”17 Is this a conclusion derived from deductive logic from certain premises that come from anthropology itself? No. It’s an inductive conclusion from all that he knows. Can we dismiss it then like Hanna does? No. We cannot dismiss it, especially since so many other anthropologists say the same thing. Cultural and religious relativism are widely accepted by anthropologists.

Let me state for the record that I have probably never met anyone who has committed the genetic fallacy. Instead, people use their background knowledge about the general reliability of an idea’s source to determine the likelihood that an idea originating from that source is true. Almost no one says, for instance, that we can never trust a particular tabloid news story because of the tabloid’s past reputation for dishonesty. What people might say instead, or intend to say, is that we probably cannot trust a particular tabloid news story because of the tabloid’s past reputation for dishonesty. People can reasonably judge the odds of an idea being true based on their background knowledge about the general reliability of the source of that idea. If an idea originates from a known unreliable source then it’s entirely reasonable to doubt any idea coming from that same source, even though we have not yet shown that idea to be false in any other way.

Take for example a person who has the paranoid belief that the CIA is spying on him, and let’s say we find that it originated from his taking a hallucinogenic drug like LSD. Since we have linked his belief to a drug that creates many other false beliefs, we have some really good evidence to be skeptical of it, even though we have not actually shown it to be false in any other way. Likewise, when many false beliefs like these are produced at a very high rate by the same source we have a good reason to doubt any beliefs arising out of that same source.

Hanna objects by arguing that the cultural origin of one’s religious faith is irrelevant to whether it is true. But the origination of one’s faith within a particular culture is indeed relevant to the probability that one’s faith is the correct one, for we know that cultures produce a wide diversity of religious faiths. Given that many of them are mutually exclusive, we also know that many of them are false. So we have very good reasons to think that cultures are an unreliable source for producing one true religion, since they have produced so many false ones. I’m arguing that the source of most people’s religious faith is an unreliable one, coming, as it does, from the geographical accidents of birth. Differing cultures produce many different and irreconcilable religious faiths that cannot all be true. Sure, it’s possible there are people born into the correct religion, if we grant there is one. But possibility doesn’t count. Probability is all that matters. (pp. 101-104)


John W. Loftus is a philosopher and counter-apologist credited with 12 critically acclaimed books, including The Case against Miracles, God and Horrendous Suffering, and Varieties of Jesus Mythicism. Please support DC by sharing our posts, or by subscribing, donating, or buying our books at Amazon. As an Amazon Associate John earns a small amount of money from any purchases made there. Buying anything through them helps fund the work here, and is greatly appreciated!