I rambled on at length about motte and bailey doctrines in a previous post. Suffice to say that this tool of critical thinking is more than a little problematic. That said, like a lot of fallacy labels and comparable forms of critical, the label of a ‘motte and bailey doctrine’ has a lot of intuitive appeal. Properly used, it might even help us identify erroneous reasoning and communicate something about the errors in question.
The question is, how best to use this criticism in practice?
I’d say that you start by asking these questions:
- What is the motte? Note that most discussions of this subject seem to assume that the motte variation of a given position is true (even a ‘trolls truism’ to use Shackel’s language), but I’m not sure that this need always be the case. It seems to me that it would suffice to find a variation in a position that is relatively easy to support and hence likely to be accepted as true. One could always hold out the possibility that the motte is also wrong in the end.
- What is bailey? Here, I do think it an essential feature of the bailey that it should be demonstrably false, or at least highly repugnant to one side of a given debate.
- What is the difference between them? (Note that if that difference matters, one should be able to show that the motte does not actually entail the bailey. It’s only a motte and bailey doctrine if the shift between them is capricious. If, on the other hand, the bailey is logically entailed by the motte, you may have the beginnings of a reductio ad absurdum, using the bailey as the grounds for deducing an absurd conclusion from stronger position.)
- Are you facing a genuinely capricious shift between the motte and the bailey? It’s not enough to be aware of different variations of the same position. What makes these doctrines a problem is the duplicitous shift from one to the other at the convenience of the doctrines proponent(s). This can occur because an individual is making the shift herself, either during the course of a specific argument or from one context to another. It can also occur because there is something about the social context of public debate that generates relatively consistent differences between the version of a given position produced for some conversations and those produced for others. The point here is that a genuine motte and bailey doctrine does merely present someone with variations in the position in question; it presents those variations in such a manner as to create an unfair burden for potential critics.
- Can you refute the bailey? Can you actually show that the bailey is wrong? If you can’t, then noting the shift between motte and bailey isn’t really going to get you anywhere.
- Are you missing anything? As with any fallacy accusation, it’ always worth considering whether or not there is something about the context of the issue at hand that makes reasoning that would normally be erroneous relevant after all. There is no formula for this, but many of the the standard fallacies come with variations that are actually reasonable arguments. (Alternatively, they parallel reasonable arguments which could easily be mistaken for their fallacious variants.) The notion of a motte and bailey doctrine is no exception to this problem.
- Are there better ways of pointing out the problem? For example, the problem of a motte and bailey doctrine could be addressed by leveling the accusation that its proponent(s) are engaging in equivocation or amphibology. If saying this will give you a cleaner counter-argument, then that may be the way to go. If that is not the case, or if you really want to underscore the strategic manipulation, then perhaps it’s best to deploy the accusation that someone is advocating a motte and bailey doctrine.
If after answering all these questions, you think you are in a position to address a position by calling it out as a motte and bailey doctrine, then go for it! Your answers to questions 1-5 should probably find their way somewhere into your account of the issue. Questions 6 and 7 have been effectively answered in your decision to make the criticism in the first place.