Topic tonight: final chapter on informal fallacies, in this case, under the heading of adequacy (vs. acceptability or relevance), concluding with the usual line up of causal fallacies (post hoc ergo propter hoc, confusing cause and effect, and common cause). Everyone had a good example from their own experience of at least one of the fallacies, only some of which would be printable here. To tee up the discussion we had also read some famous passages from Hume on causation (or better, on the problem of positing necessary connexions between alleged causes and effects) from An Enquiry Concerning Human Understanding. New man in the group who’d not gotten a copy of the text (and never will, at this point. I will instead send him photocopies of what’s left to cover via the librarian who may or may not actually get the material into his hands*), sat quietly for the first 40 minutes or so. We’d been talking about the nefarious exploitation of Humean reasoning by the tobacco industry’s spokesmen before Congress in the 60’s, and contrasted it more modest scientific reluctance to conclude that correlation is causation.  What a wallop when he did speak: “Hume was right…at least about the mind’s need to project a cause between A and B just based on A and B often coming together. And I can’t tell you how many ways the wrong projection of causes has messed with both the general public’s understanding of HIV, and among people at high risk for contracting HIV. The rampant misunderstanding about who is at risk and why has led people to reject good scientific authority about how to educate for prevention. We need to be so much more careful in the conclusions we draw and how we talk about what we do and don’t know.” Lucky stars! — he just finished a 10 day course on HIV peer education, with a focus on epidemiology.

He filled in some interesting (if depressing) detail about what groups have seen the greatest rise of infection from 2010-2015 (the most recent full data set), at the same time throwing into sharp relief my own low expectations for what these men as a rule might or do know. And it’s not as if that doesn’t happen at just about every single meeting: that’s how entrenched the assumptions are, at least in my ancient brain.

I am also never not taken aback by the loud speaker’s “Go back!” announcement at precisely 8:30, and reminded of the luxury I often exploit in my college classes by stealing a minute or two (okay, or five) over time to let whoever is talking finish making the point. In this case the men must do so literally on their way out the door. Parting question tonight: how do you square the charge of over simplified cause with the demands of Occam’s Razor?

Such a great question to start out with next week!

* Will have more to say about this in my next post.