so far as I know, [BIDMAS] is a creation of some educator, who has taken conventions in real use, and extended them to cover cases where there is no accepted convention. So it misleads students; and moreover, if students are taught PEMDAS by rote without the proviso mentioned above, they will not even get the standard interpretation of a−b+c.
Even better: BODMAS is widely attributed to Achilles Reselfelt. However, it seems that this person doesn’t even exist! Apparently the earliest known version of that acronym is from 1945.
This article gives the best study of the origins that I’ve found.
What many people don’t realize is that the “rules” we teach are only an attempt at DESCRIBING what mathematicians did for a long time without explicitly stating what rules they were following. They do not PRESCRIBE what inherently must be done, a priori. In just the same way, English grammar came long after English itself, and has sometimes been taught in a way that is inconsistent with actual practice, in an attempt to make the language seem perfectly rational.
Oh damn, I like that English grammar comparison, because that’s exactly the same comparison I made myself just a few minutes ago. (Well, almost. I was comparing to dictionaries and word definitions and criticising prescriptivism. But it’s similar.)
Absolutely rekt.
Even better: BODMAS is widely attributed to Achilles Reselfelt. However, it seems that this person doesn’t even exist! Apparently the earliest known version of that acronym is from 1945.
This article gives the best study of the origins that I’ve found.
Oh damn, I like that English grammar comparison, because that’s exactly the same comparison I made myself just a few minutes ago. (Well, almost. I was comparing to dictionaries and word definitions and criticising prescriptivism. But it’s similar.)