Modus pon‑something

Modus Ponens

  1. 1.If P, then Q.
  2. 2.P.
  3. 3.Therefore, Q

Have you ever tried teaching modus ponens to someone who doesn’t get it? Well I have, 3 hours a day, 5 days a week, at the University of Edinburgh. You begin, naively, with the syllogism itself.

Teacher:“If P is true, then Q is true. Now, let’s say P is true. What can we say about Q?”

Student:“I’m confused. What’s going on with all the Ps and Qs?”

I try explaining P and Q and how they work as placeholders, but I have no luck. My algebra analogies are met with dumbfounded and anxious stares. I decide to make it more concrete.

Teacher:“Okay, forget P and Q. Let’s try with some specific statements. If it is raining, then the street is wet. We know it’s raining, so what can we deduce from that?”

Student:“The street is wet!”

Progress? Perhaps. I run through various examples and it seems to be clicking. I then suggest that all the examples have the same form and reintroduce the Ps and Qs. Some students nod. Others stare blankly. In the second lesson I try to introduce a logical fallacy to test their understanding:

Teacher:“If the street is wet, does that mean it is raining?”

Student A:“No, the street could be wet for other reasons, like I could have spilled some water.”

So far so good. But then it all comes crashing down.

Student B:“Hey, but wait, maybe the street wouldn’t be wet if there was a cover over it?”

Student C:“Yeah, how do we know when the street is wet and when it isn’t?”

I’ve clearly screwed up somewhere, but where exactly I cannot tell. I go around in circles like this for a while but always get drawn back to the same inability to move beyond concrete examples. Eventually I surrender and focus on the 20% of impatient students who do the reading and can understand modus ponens. The rest stare idly into space or surreptitiously browse social media on their laptops.

The course organiser claimed that anyone can understand basic syllogisms in our introductory meeting, but it was clear he was having similar problems to me. He stared at some distant point behind me to my left: “I don’t get it, I feel like with enough work everyone can get this…”

What has happened, and I do not think this is a very controversial opinion, is that British universities have widened admissions beyond what is sensible. The Universities of Edinburgh and Glasgow are cash-strapped and need the tuition fees from more students. In the words of one extraordinarily cynical colleague: “there are still pupils who want to come here but cannot get in based on their grades. We can grow our way out of these problems by taking them in.”

Many of the current students seem to do no reading and struggle to understand the exercises they were meant to pre-prepare. In my Unjustified Enrichment class, I had the following interaction:

Teacher:“Right, let’s do Part 1, section (b). Do you think Johnson has a claim in unjustified enrichment against Celeste?”

Student D:“Nah, he’s already got enough money.”

This was not a joke. This was a serious response to my question, and the student was baffled when I tried to explain that personal wealth is not a legally relevant consideration. Presumably there are students weaker than student D, but I am struggling to imagine them in the context of a university law course.

Teaching modus ponens to students who cannot, and do not want to, understand it is a complete waste of time. It also ruins the experience of the students who can understand modus ponens. The top 20% must either trod along slowly with the rest, or uncomfortably dominate a conversation filled with silent, blank faces. Most of the other academics agree, although rarely in so many words. An exception is an insurance law specialist who expressed the following over dinner: “I think we need to come to terms with the fact the old university, where students wanted to learn, is gone.” This was met with sad, affirmative nods.

Well I don’t want to come to terms with this! Since when did we all move to crazy town? But equally the thought of teaching modus ponens over and over to incapable and uninterested students is unbearable, and there is no way, from the lowly position of a university tutor, to change anything structurally. My proposals for more internal ability differentiation, like the classes of a school, were ignored and dismissed as unfair.

So I quit.