Propositional Attitudes and Flying Saucers

I talk about propositional attitudes and how it’s important to teach students that there is a claim and a position on that claim and the two things are separate. This is important for many reasons, but one is that without understanding the separateness of a position from the claim people often play a shell game, forcing someone who claims something is unlikely to prove it is impossible. Richard Feynman deals with this here:

The reason Feynman is frustrated is the model other people are using is that there is a position specifically on flying saucers that is separate from all other claims. But as Feynman points out when he says flying saucers are unlikely of alien origin the way he conceptualizes that is relative to other explanations.

This was one of the great insights of Toulmin in The Uses of Argument — terms such as “likely”, “probably”, “unlikely” and such are generally about the position of a claim relative to other related claims. If I say a person probably crashed because they were driving while tired I am signaling that I have no explanation that significantly competes. If I say they may have crashed because they were tired, I am signaling either other explanations are competitive or I lack necessary information. If I say presumably a person crashed because they were tired, I’m signaling that if assuming no new evidence comes to light, no other explanation comes close.

What you are defending in terms of a claim is not the claim itself. Rather, as we have been stating here, you are defending what the most reasonable position on that claim might be. That’s always done in a larger context. Are things best explained by human error, knee-jerk government secrecy, foreign technology, or alien life? There is no granular evaluation of that, you must look at all to come to a conclusion.