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Tuesday 26 April 2016

Onus Probandi, Assertionism and Peer-review.

Good morning, ladles and jellyspoons.

In the wake of the hyperbolic, hysterical travesty that was the Boaty McBoatface saga, I have, after many years of resistance, succumbed to the double-edged Damoclean temptation of a sojourn into the Twitterverse. I've avoided it precisely because I have the worst case of SIWOTI syndrome in the recorded history of the universe since the invention of Tim Berners-Lee, especially when the WOTI is, in my esteem, harmful.

It should come as no surprise to learn that I've managed to find some WOTI in fairly short order, in this case in the form of a column on the website of the Daily Telegraph and a resulting series of tweets and other interactions.

I had wanted to use this post to continue on pre-Planck cosmology, but thought it worth picking this apart a little.

The article itself is this one, headlined Forget my son - I'm the one in exam stress hell, penned by Allison Pearson, known to some as the author of I Don't Know How She Does It.

Much of the article is unobjectionable. Liberally sprinkled with apposite anecdotes (see below for caveat regarding this), and a tone of exasperated but good-natured humour, with some reasonably decent advice for parents enduring the slings and arrows of teens going through one of the most stressful times in their young lives. Then, however, comes the following:

When they made the exams easier to pass they also made perfection attainable. Diligence is all. Fine if you’re a swotty, well-organised girl, not so good for testosterone-plagued slugabeds.

Now, the diligent reader will spot the issues with this without direction. Setting aside the notion of the attainability of perfection, which has some logical problems all its own, the real issue lies in the latter portion. I'll come back to that shortly, but here's the opening salvo:

A couple of assertions in there, not least the one saying 'all the evidence suggests...'

There's an extremely common fallacy committed in public discourse known in rigorous circles as onus probandi, closely related to the fallacy of bare assertion, both of which are discussed in a previous post. Onus probandi is the shifting of the burden of proof. In essence, this fallacy is committed when, rather than supporting one's own claim, the claimant insists that the skeptic prove it false.

It's up to the person erecting a claim to support that claim. Failure to do so commits one of the two above fallacies, dependent on the circumstances. The reason for this should be fairly obvious, namely that skepticism is the rebuttable position for any given claim.

In the first assertion above by Ms Pearson, no good reason has been given to accept the claim 'that boys lag behind girls in organisation skills and exam results'. This commits the fallacy of bare assertion. It's easy to see how this is related to the onus probandi, because the fallacy of bare assertion is essentially onus probandi by proxy.

Dr Weinstein then raises the motivating point for her initial interjection, and it's a good one. She asks Ms Pearson whether she thought the veracity of this claim (not contested for the moment) was sufficient reason to promulgate stereotyping in a national newspaper.

Stereotyping is another common fallacy (hasty/sweeping generalisation), but this one actually has measurable negative consequences in the real world, and the more people who buy into a given stereotype, the more destructive it is.

In this instance, she's voicing a commonly-held perception that girls are generally better organised and less indolent than boys, and that this is reflected in their exam results. Whether this assertion is actually true is almost beside the point for the purposes of Dr Weinstein's point, which is that perpetuating such a stereotype can be harmful and, worse, stereotypes are self-perpetuating[1] (this is how it's done, incidentally: Ed).

Ms Pearson defends her article, saying that 'it isn't stereotyping', which reveals another problem with stereotyping, which is that we often don't even realise we're doing it!

Of course, the scientifically literate among us realise that this is just another manifestation of our exceptional pattern-seeking software, which has had deep consequences to our evolutionary history, not least that it's lasted as long as it has, but I digress.

She goes on to assert 'it's science'. Here's the fallacy again, but this time with a smuggled in argumentum ad verecundiam (appeal to authority).

Moving on to the follow-up:

This is a quite beautiful fallacy committed by Ms Pearson, the argumentum ad populum in all its glory, along with a glorious feedback loop of 'reasoning' whose radius is related to its circumference by a multiple of 3.14159 (excuse the tautology, it was for emphasis).

It's true because mothers loved it, and mothers loved it because it's true. Can you say 'circular'? I know you can!


Of course, at this point the inner gobshite took over, and I interjected:


SIWOTI! That's my excuse and I'm sticking to it.


Anyhoo, there was another exchange, this time on another platform: