In my previous post, “The Republican Modus Tollens”, I pointed out that arguments apparently having the valid form (1) If P then Q (2) Not-Q (3) So Not-P
allow for serious irrationality when P represents a matter of well-confirmed scientific theory and Q represents a prescriptive policy preference or a tenet of religious faith. So, to use one of the examples from my previous post, we have arguments about climate change that seem to be guided by the following pattern of thought-
(1) If climate change is occurring, then we should regulate CO2. (2) We shouldn’t regulate CO2. (3) So climate change isn’t actually occurring.
Of course, probably no opponent of climate change has ever explicitly made just this argument. My point is that the arguments they do make are evidently motivated by some such pattern of thought. Representing the pattern this way makes clear that they are often reasonable enough to recognize that if climate change were occurring, then we (perhaps) should regulate CO2. The problem is that they also very strongly desire not to regulate CO2 (perhaps for quite defensible reasons, such as worrying about the economic effects of such regulation), and this very strong desire against a possible policy choice, along with the normally valid modus tollens pattern of thought, leads them irrationally to deny a well-confirmed theory. In order to do so, they must massively over-weigh evidence contrary to climate change, sometimes fantasize about global conspiracies of scientists, and so on. It is this last move – the irrational denial of a scientific theory – that indicates they are being guided, at bottom, by strongly held policy positions and this modus tollens pattern of thought, or something similar to it.
Click for Full Text!
