Why Would a Math Teacher Punish a Child for Saying 5 x 3 = 15?

[Chan790]

245. Even if that were the true lesson...the teacher is still the one that is wrong.

5x3 is to me, and always has been, 3 groups of 5, not 5 groups of 3.

The problem here isn't really O of O (I can PEMDAS like a motherfucking riot)...it's really math/semiotics conflict. People who are forced to work contrary to their math/semiotic tendency don't learn higher math better...they tend to be totally incapable of learning higher math at all. It's the same problem we see in rats and primates that are surgically altered in adolescence or adulthood so that the part of the brain that controlled the left hand now controls the right...they don't become left-handed. They typically lose the functions of both hands altogether despite there being no neurological failure because their brain doesn't adapt, it fights itself every step of the way to reconcile now-reversed outputs to hard-wired processes. (Most of them also lose the ability to "walk" actually. (Side-note: never date a neurology researcher, you will learn disturbing things like "there's a guy at work decapitating chimps so they can experiment on successfully reattaching a severed head." and "0.5% of men experience orgasmic sensation in their non-dominant hand during sex and we don't know why but they're 3x more likely to die if they develop brain cancer.&quot ) This is also why many people panic-steer a car in reverse in the wrong direction...because the correlation between which direction the wheel goes versus which direction the car goes is contrary to their intuition and functions only as a learned-behavior that gets overridden by instinct as panic and stress hormone levels rise.

The array in the next question is just as arbitrary as it depends not on order of operations but again how one reads. Some people organize data vertically and some people organize data horizontally. There is nothing in mathematics that necessitates one to organize things one way over the other...the concepts of left and right, horizontal and vertical, up and down are all non-sequitur.

iiii
iiii
iiii
iiii
iiii
iiii

isn't commutative to

iiiiii
iiiiii
iiiiii
iiiiii

From a visual data standpoint. It's actually identical. 4x6 is expressed by either array depending on if you first organize data vertically, then horizontally...or vice versa. They're both 4 groups of 6...or 6 groups of 4...but you probably (like virtually everybody) see one as feeling "correct" for 4x6 and one as 6x4 and it's hardly universal. It's analogous to something that blows people's minds: that there is no "up" in space in any strict sense. Up is perceived in space as the direction towards the top of your head...and that's only the same direction as it is on Earth about 1/129,600 of the time.