Believing Bullshit: How Not to Get Sucked into an Intellectual Black Hole by Stephen Law Page B

of inferiority (producing perhaps the need to prove to himself that he dared to commit some crime), and so did the second man (whose need was to prove to himself that he dared to rescue the child).
     
    Popper found he couldn't think of any human behavior that wouldn't fit either theory:
It was precisely this fact—that they always fitted, that they were always confirmed—which in the eyes of their admirers constituted the strongest argument in favor of these theories. It began to dawn on me that this apparent strength was in fact their weakness. 12
     
    So Popper thought these two psychoanalytic theories were unfalsifiable, and for much the same reason. Popper also thought that Marx's theory of history was unfalsifiable, but for a different reason. According to Popper, unlike Freud's and Adler's theories, Marx's theory started out as a falsifiable theory. In fact, it made some rather risky predictions about how history would unfold. For example, it predicted the character of a coming social revolution (for example, it predicted the revolution would happen in an industrially advanced society such as Britain). However, this prediction turned out to be largely incorrect (there was a revolution, but it did not take place in the way Marx predicted—it actually happened in industrially backward Russia). Marx's theory was therefore falsified. Rather than accept this, Marx's followers employed an immunizing strategy, reinterpreting theory and evidence so that the theory continued to fit the evidence after all:
Instead of accepting the refutations the followers of Marx reinterpreted both the theory and the evidence in order to make them agree. In this way they rescued the theory from refutation; but they did so at the price of adopting a device which made it irrefutable. 13
     
    Dave's Immunizing Strategy
    Let's now return to Dave's theory that dogs are spies from the planet Venus. Mary and Pete tried to falsify Dave's theory, but each time they tried, Pete came up with yet another explanation for why his theory is, after all, consistent with the evidence. While some of Dave's moves are rather ad hoc in nature, others are not. His suggestion that the dogs' transmitters are located in their brains does in fact lead to a new test —we could look inside dogs' brains to check whether there are any transmitters. However, when no transmitters show up, Dave just makes another adjustment—he says the transmitters must be made of organic material indistinguishable from brain stuff. So while not every immunizing move Dave makes is ad hoc, his overall strategy renders his theory unfalsifiable. So, yes, today's Young Earth Creationists can say, “Our theory has not been falsified!” But that's only because, given their immunizing strategies, it cannot be.”
    Clearly, Dave's theory suffers from the same problem that Popper found with Marxism. Dave's theory starts off as potentially falsifiable. However, once it is falsified, Dave develops an immunizing strategy that makes it unfalsifiable. Every time his theory runs into trouble with the evidence, Dave just makes another modification to deal with it: to make it fit the evidence after all.
    As should now be clear, the version of Young Earth Creationism outlined above is also unfalsifiable, and for much the same reason. The theory that the earth was created just as described in Genesis starts out as a falsifiable theory. Indeed, it is straightforwardly falsified by a mountain of evidence. In response to the evidence, proponents of Young Earth Creationism, like Dave, then devise ever more ingenious moves to account for it. Once they have embarked on this strategy, their theory becomes unfalsifiable. It's the strategy developed to defend the core theory, rather than anything about the theory itself, that makes it unfalsifiable. So, yes, today's Young Earth Creationists can say, “Our theory has not been falsified!” But that's only because, given their immunizing strategies, it cannot