Moving goalposts

As I said before, I think it's important that we not blindly apply logical fallacies as if they were infallible. Well the "moving goalposts" fallacy is one that I think should not be considered a fallacy at all, though for different reasons from the previous examples. Most skeptics would disagree with me, so I'll argue my point.

The "moving goalposts" fallacy starts out when, in a debate between Alice and Bob*, Alice sets a "goalpost" for Bob. Alice says, "If you can do X, you will have proven me wrong." Bob proceeds to do X. Alice seems to forget what she had previously said, and now says, "If you can do Y, I will eat my words." Bob proceeds to do Y. Alice again seems to forget, and now says, "If you can do Z, I will put my foot in my mouth." Bob becomes frustrated and gives up.

The idea behind this fallacy is that even though Bob has disproven Alice's claim twice, Alice does not recognize that she has lost. If action X does in fact disprove Alice's claim, and if Alice does not change her claim, then, yes, Alice is in the wrong. She is also in the wrong if she merely changes the name of her claim, or otherwise equivocates what she really thinks. She is doing the rhetorical equivalent of sticking her fingers in her ears and singing loudly, "I know I'm right and you're wrong because I haven't heard any evidence!"

But I think that in practice, this is not what usually happens. In practice, Alice changes her position. Her change in position may have been very slight, and implicit, but it is a change nonetheless. Perhaps she has decided that X does not in fact disprove her original claim. Other times, Alice may change her original claim slightly to accommodate the evidence from X. I do not see why changing one's own position should be considered in itself fallacious.

However frustrated Bob may be, he must provide a new argument against Alice's new claim. Either that, or Bob may point out that his previous arguments still apply to Alice's new claim. There are innumerable wrong positions Alice could take. Must Bob counter every single one that Alice decides to take? Yes, at least if Bob wants to convince Alice. Perhaps he can think up an argument that counters all possible positions Alice could take.

I think what people really find frustrating about moving goalposts is that they want their opponent to definitively lose. Bob wants Alice to publicly admit complete defeat. But instead of admitting defeat, Alice merely decides to replace her old claim with a new, slightly different one. But I would say that the desire for a clear surrender is an emotional one. In a way, Alice has admitted defeat by discarding her old position. She just hasn't done it loudly or theatrically. They seem to fantasize about their opponents saying, "I was a fool, and you are wise." Take what you can get, I say. The real goal of debate isn't victory, it's truth.

Rather than just talking about Alice and Bob, allow me to substitute a real life example. Many people think of "Intelligent Design" as being Creationism with a moved goalpost. Well, I think that means you can't always use the same arguments against the two. On the one hand, you could argue against both ID and Creationism by pointing out that Evolution is really one of the best established theories in all of science. On the other hand, you couldn't argue against ID by pointing out evidence of a 4.6 billion year history, because (as far as I know) ID already accepts the age of Earth. ID has a ton of problems, but it's still a slight step above Creationism. I just don't see the goalpost-moving as being in itself fallacious. Are people not allowed to change their minds, to improve their own positions?

Well, I guess in this case it's reasonable to want a definitive loss, but that's only because ID isn't so much a real debate as it is a silly PR machine.

*In case it isn't clear, Alice and Bob are just two names I am using to represent any two people in a debate. Physicists seem to be fond of using these two particular names in thought experiments, so I will do the same.