But is zero a positive number?
Comment on Zero to hero
CodexArcanum@lemmy.world 11 months ago
I’d learned somewhere along the line that Natural numbers (that is, the set ℕ) are all the positive integers and zero. Without zero, I was told this were the Whole numbers. I see on wikipedia (as I was digging up that Unicode symbol) that this is contested now. Seems very silly.
Magnetar@feddit.de 11 months ago
threelonmusketeers@sh.itjust.works 11 months ago
Weird, I learned the exact reverse. The recommended mnemonic was that the whole numbers included zero because zero has a hole in it.
MBM@lemmings.world 11 months ago
I think whole numbers don’t really exist outside of US high schools. Never learnt about them or seen them in a book/paper at least.
reinei@lemmy.world 11 months ago
Actually “whole numbers” (at least if translated literally into German) exist outside America! However, they most absolutely (aka are defined to) contain 0. Because in Germany “whole numbers” are all negative, positive and neutral (aka 0) numbers with only an integer part (aka -N u {0} u N [no that extra 0 is not because N doesn’t contain it but just because this definition works regardless of wether you yourself count it as part of N or not]).
CodexArcanum@lemmy.world 11 months ago
I wouldn’t be surprised. I also went to school in MS and LA so being taught math poorly is the least of my educational issues. At least the Natural numbers (probably) never enslaved anyone and then claimed it was really about heritage and tradition.
RandomWalker@lemmy.world 11 months ago
Natural numbers are used commonly in mathematics across the world. Sequences are fundamental to the field of analysis, and a sequence is a function whose domain is the natural numbers.
You also need to index sets and those indices are usually natural numbers. Whether you index starting at 0 or 1 is pretty inconsistent, and you end up needing to specify whether or not you include 0 when you talk about the natural numbers.