Tuesday, 6 January 2009


While reading yet another book that presents one or more acronyms as an aid to remembering important points (this time, in "Pragmatic Unit Testing in C#"), I came up with my own acronym to express my thoughts about this. I call it Richard's CRAP rule of didactics:
  • Can't
  • Remember
  • Acronyms
  • Psomething... oh crap, where did I put that book...
My point is, that if you are able to remember not only what each letter stands for, exactly (is the I in ACID1 for Independence or Isolation...), but you can also give a detailed explanation of what each short bullet point really means (e.g., how is Atomicity different from Consistency and why are both needed), it means that you already have a very firm grasp of the subject. So while acronyms may be a useful device for not forgetting things once you understand them, they are fairly useless for the beginner.

However, it's worse than that; if they were only useless, they could simply be ignored. But the fact is that acronyms are quite often used precisely in texts for beginners, and more often than not they are used as the basis for the presentation of the material: first the list of bullet points is presented, and then a section or chapter is dedicated to each. I contend that this is exactly the wrong way to present any subject. It wastes pages (and the reader's time) on what becomes a mere shopping list, forgotten as soon as we move on to the next chapter, instead of using that space in a more constructive way to actually help the reader build an understanding of the subject to the point that he may invent his own acronyms if he needs them. (Finishing the chapter by suggesting such an acronym is quite OK.)

So here's a new year's promise: following this, I will never again (except for comical effect) use an acronym as the starting-off point for a text.

1) The ACID rule for databases: Atomicity, Consistency, Isolation, Durability. (Even I could not remember the last two verbatim without peeking, and I am quite familiar with database theory.)


Janne Morén said...

One dangerous example I fall prey to:

There is an acronym rule taught in Swedish high school chemistry about which order to mix and acid and water: SIV, or "Syra I Vatten" (Acid In Water).

Of course, "Siv" is a female first name, so not exactly obviously connected to the meaning of he acronym. As a result I tend to misremember the rule as VIS, "Vatten I Syra" (Water In Acid) instead, since "vis" means "wise" and of course you're wise in following the rule (except you aren't of course).

Worse, since i know I tend to mix these two up I end up not trusting my own memory whichever I think is right - It's SIV, right, except I always get this wrong so it's VIS, but that sounds too easy so perhaps it was the other way around after all... I actually had to look up the correct order for this comment.

And of course we have the old joke that "PCMCIA was the IT industry's answer when criticized of using three-letter acronyms for everything."

Richard said...

Ah yes, the SIV rule. I think I remember an illustration from a chemistry textbook, with the caption "SIV says: don't be VIS (wise)", which makes sense when you read it, but since it commits the pedagogical crime of speaking in negatives, it will not help you a year or two later when you desperately try to remember which part was the "don't". (And remember, kids: your face will melt if you get it wrong.)

A good, brief, explanation like this one is much easier to remember correctly in the long run.