When people claim that 0.999... is not equal to 1, mathematicians get confused because they don't understand why students don't understand, even after a simple proof.
It's because you guys are proving features of decimal notation with algebra. It's bad pedagogy. It creates cognitive dissonance.
If different notation means a different number is the starting axiom (an implicit, unconscious framing), then proving that they are equal makes algebra seem inconsistent.
A conceptual separation between decimal notation and the number it refers to should be the first thing.
Teaching decimal notation separately, and not as part of elementary algebra, and making that distinction clear is, in my humble opinion, the only pedagogically correct way.
Does anyone disagree?
mađť•Źpool
npub1p7…fkglz
2025-08-05 10:53:50 UTC
in reply to nevent1q…3kq9
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wss://relay.momostr.pinkPublished at
2025-08-05 10:53:50 UTCEvent JSON
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"content": "When people claim that 0.999... is not equal to 1, mathematicians get confused because they don't understand why students don't understand, even after a simple proof.\n\nIt's because you guys are proving features of decimal notation with algebra. It's bad pedagogy. It creates cognitive dissonance.\n\nIf different notation means a different number is the starting axiom (an implicit, unconscious framing), then proving that they are equal makes algebra seem inconsistent.\n\nA conceptual separation between decimal notation and the number it refers to should be the first thing.\n\nTeaching decimal notation separately, and not as part of elementary algebra, and making that distinction clear is, in my humble opinion, the only pedagogically correct way.\n\nDoes anyone disagree?",
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