[HN Gopher] How the modern world arose from imaginary numbers ___________________________________________________________________ How the modern world arose from imaginary numbers Author : CapitalistCartr Score : 23 points Date : 2022-02-10 12:13 UTC (10 hours ago) (HTM) web link (nautil.us) (TXT) w3m dump (nautil.us) | adityapatadia wrote: | This is one video which shows history of imaginary numbers and | their usefulness in current times. | | It's from Veritasium: https://www.youtube.com/watch?v=cUzklzVXJwo | gumby wrote: | "Imaginary" was an unfortunate choice of word. Positive integers | and rationals feel "legit"* to most people, even (or especially) | the non-mathematically trained. | | But "imaginary" numbers are no more or less legit than, say, | transcendental numbers. But in middle school you learn this | confusing thing and maths starts to fall off the rails. | | * Had to find a synonym for "real" here. | jdrc wrote: | Yeah we should stop using the word imaginary, and just call | them iNumbers (sorry Apple) | Qem wrote: | I like to call them "double-barreled numbers". I never liked | the term "imaginary", because that gives mystical | connotations and even hamper understanding, in my opinion. | intrepidhero wrote: | That's what I've finally settled on in my mind. Since we use | imaginary numbers to model and measure real phenomenon, they're | not imaginary in the sense that I would usually use that word. | There's got to be a better name... Transcendental complement | maybe. | viktorcode wrote: | I highly recommend video by Sabine Hossenfelder [1] on this | topic. She's explaining the topic in layman terms, starting from | what does it mean to exist (or be real) in physical sense. | | Complex numbers, as useful as they are, just an abstraction, a | tool which can be replaced with different forms of calculations. | That makes the question of "reality" rather complex (pardon the | pun). | | [1] https://www.youtube.com/watch?v=ALc8CBYOfkw | Psyladine wrote: | For those interested I also highly recommend Veritasium's | video[1] as an excellent explainer as well, especially | regarding the roots of imaginary/complex numbers in geometry. | | [1] https://www.youtube.com/watch?v=cUzklzVXJwo | [deleted] | nuncanada wrote: | Mathematicians have been constantly been giving bad names do | their concepts... Imaginary Numbers is one of the atrocious ones, | Imaginary Numbers are part of the fabric of our reality... | Meanwhile Real Number were axiomatized in a way that creates | completely unrealistic numbers, "ghost-like" numbers, numbers | that can never be given a name... The first course in Analysis is | ridden with examples of Continuous Functions that are not | continuous in any sense humans would consider ever it... | dandanua wrote: | Life is complex - it has real and imaginary parts. | 1970-01-01 wrote: | I've been calling them invisible numbers most of my life. It | makes much more sense. | Agamus wrote: | I'm not an expert here, but truly interested to hear responses to | this question. | | To say that 1+1=2 is "true", does that not require a corollary in | "reality" to something fundamental that can be called a "one" | object? I believe this is called mathematical constructivism. | | Imagine, hypothetically, that we cannot identify something that | is physically fundamental and individual. My question is whether | any mathematics in that scenario could be considered "true" | without such constructivism, in other words, without a physical | correspondence to an unquestionably, physically fundamental "one" | object. | hgomersall wrote: | There is a persuasive school of thought that argues exactly the | opposite, that imaginary numbers are not real | http://geometry.mrao.cam.ac.uk/1993/01/imaginary-numbers-are... . | topaz0 wrote: | I'm familiar with (and partial to) the geometric algebra | literature, but I think it's a bit disingenuous/clickbaity to | say that it implies imaginary numbers aren't real. I think of | it as meaning that the algebra of the imaginary numbers arises | as a slice through a more useful, bigger algebra. | hgomersall wrote: | Yes, I think it's rather tongue in cheek. It's probably not | defined as clickbait since it was written in '93! | dboreham wrote: | This is only mentioned in passing in the article, but the penny | dropped for me when I read somewhere else that you should first | think about negative numbers. They seem pretty real, but they're | not. There's no negative quantity in nature. You can't have -5 | rocks. Negative numbers are just the solution to equations of the | form x + n = 0. Now after you let that sink in, imaginary numbers | don't seem so weird after all. Just another kind of number | defined as the solution to some equation. | TheOtherHobbes wrote: | You can owe someone five rocks (or dollars, to make it only | slightly less abstract.) | | You can go five miles east instead of west (more of a vector, | but still makes sense if your movements are limited to a number | line instead of a number plane). | | Imaginary numbers are more of the same with a twist. i is just | a pi/2 rotation on a plane instead of a negative number, which | can be thought of as rotation by pi on a line. | | The big mistake with imaginary numbers is calling them | imaginary. There's nothing imaginary about them. They're a very | specific kind of operation which can be expanded with very | little thought or effort to complex numbers, which have | incredibly useful properties in engineering. | | Calling them "imaginary" is cripplingly confusing for almost | everyone, and many never get over it. | redler wrote: | You could have five exactly rock-shaped holes in the ground, | and by adding seven rocks, only two remain above the surface. | mettamage wrote: | I disagree. | | > You can't have -5 rocks | | You can have 5 rocks destroyed in the future. That to me, is | what -5 physically means: a guarantee that the object | associated with the number will be eliminated out of existence | in the future and decrement the negative number by 1. | | Some people call it debt, but to me, emotionally that word | feels too financial. So I prefer "a guarantee to be eliminated | out of existence in the future ", or something like that. | | Conversely, 5 cows means: 5 cows currently in existence. | | 5 cows - 5 cows means: I see 5 cows and now they don't exist | any more and there is nothing. | | I wish my math skills were better, I am optimistic that I'd | find a similar thing for imaginary numbers and maybe even | complex numbers. | | With that said, I do get where you're coming from and I find it | a compelling perspective as well. It's simply that I feel the | perspective I described as well. | easywood wrote: | >> You can have 5 rocks destroyed in the future You have 5 | rocks now, and zero rocks in the future. At no point are | there negative rock-shaped holes in the fabric of space. The | parent's comment still stands, he is talking about reality, | not our mathematical interpretation of it. | marcus_cemes wrote: | > You can have 5 rocks destroyed in the future. | | Exactly, you use it to store some information that has no | real quantity but may be converted to a real quantity in the | future through some other process. | | I'm a polytechnic university student, we use imaginary | numbers extensively in all sorts of places, especially | whenever there is any oscillatory behaviour, such as an | electrical signal or a light wave. A complex number is just a | two-dimensional vector with real/imaginary components, whcih | provides an amplitude and a phase (angle). An oscillating | sinusoidal signal/wave may appear to be zero and completely | static if you freeze time at the right moment, but as time | progresses, it will continue oscillating, like a swing in a | park. | | In a way, the magnitude represents the built up "momentum" of | the system, whilst the real quantity is the immediate | physical value at any given point in time (given by the | phase). The amplitude is always the same at any given moment, | even when the swing is vertical, it has momentum which will | help it reach its maximum height. | | Personally, I still think they are just "invented", but I | think the vast majority of engineers much prefer them to the | alternative, manipulating trigonometric functions (every | engineer's nightmare). They're a neat way to represent the | exchange of potential and mechanical/electrical energy with a | single value and some simplified mathematics (this is an | engineer's, not a mathematician's, point of view). Like | negative numbers, we could have chosen to have two positive | quantities, balance and debt, instead we find use in merging | these definitions, whether negative values make sense or not. | We have become used to to negative numbers representing the | "inverse" action, which makes sense when representing a | phyiscal quantity such as velocity. | taco_emoji wrote: | You're not actually disagreeing. OP is saying the negative | numbers are useful _conceptually_ , which is what you're | demonstrating here. | | Also thinking about a number line is useful when talking | about both negative numbers AND complex ones: negative | numbers are to the left of 0, but complex numbers are _up and | down_ from the number line. | phendrenad2 wrote: | Imaginary numbers are just a shorthand way of representing things | in nature that relate to one another via the sine function, for | example, charged particles in a magnetic field. You can bust out | calculus to describe the motion, or you can use a convenient set | of rules that represents the partially-solved equation. | nyc111 wrote: | > For some reason--whether a sense that there was some mistake, | or someone copied something down wrong, or because it was so | absurd--the manuscripts we have show that Heron ignored the minus | sign and gave the answer as [?]63 instead. | | I wonder if the minus sign was in use in the time of Heron (First | century AD). I couldn't tell from this Wikipedia page | https://en.wikipedia.org/wiki/Plus_and_minus_signs | dTal wrote: | Another way to think of it is that _all_ numbers are imaginary. | | Numbers aren't real. Platonism is wrong. Imaginary numbers aren't | "out there" somewhere. The whole system of mathematics is an | accumulated edifice of metaphors designed by human brains, for | human brains, and there's no god "behind the curtain". It's just | a tool of thought. It reflects the "reality" of the universe only | insofar as we've looked at the universe, noticed patterns, and | constructed metaphors around them. | | This is not a popular viewpoint! But it is the only | scientifically supported one. | voldacar wrote: | This is one particular point of view, and it's extremely sloppy | reasoning to say that it's "scientifically supported", given | that mathematics is not a form of science. | | There are plenty of very smart people, not just mathematicians | but also physicists & scientists who are mathematical | platonists. | dTal wrote: | There are plenty of smart people - scientists even - who | believe in all kinds of deities. | | Mathematics is indeed not a form of science. But the | existence and shape of mathematics is an observable | phenomenon, and so _meta_ mathematics - the study of what it | is and where it comes from - _can_ be studied scientifically. | How do you know mathematics exists? Well, there 's a textbook | right there. Who wrote the textbook and why? A human, | expressing metaphors inside their heads. How did those | metaphors get inside that human's head? Ah, well, that's the | interesting bit - the answer of course transpires to be "a | combination of innate ideas imprinted by genetic evolution by | natural selection, and sociology". And you don't have to stop | there, you can explore in glorious detail exactly _where_ | each idea comes from, what innate monkey-ish tendency is | being deployed, how exactly ideas like "infinity" fit in a | mind designed for finding fruit and chasing things. | | We can similarly bring all manner of religious beliefs under | the anthropological knife. It's not a pretty process though, | to the people who believe in them. | carapace wrote: | > metaphors inside their heads. | | You're begging the question presupposing the non-Platonic | viewpoint here. How do we know that metaphors are "inside | the head"? | voldacar wrote: | You are just assuming the point you're trying to prove | | > There are plenty of smart people - scientists even - who | believe in all kinds of deities. | | Okay? This is supposed to make me feel - how exactly? I'm | not inherently disdainful towards theism or theists, but if | I were, I guess your remark would make me like science | less, or something? | | > We can similarly bring all manner of religious beliefs | under the anthropological knife | | I'm not really sure we can, actually. At least not in some | kind of non-contentious, "objective" sense. I don't really | trust individual humans to give an accurate account of why | they believe their beliefs, but I trust "anthropology" and | "sociology" even less. My distrust for this on an | individual scale comes from the fact that many beliefs & | memes exist for purposes of social signalling, group | identification, etc, and it might not actually be in your | interest to know exactly why you believe what you do. | | But these auxiliary functions of beliefs, such as | signalling etc, seem to me to scale _up_ as you introduce | groups and larger-scale activities such as "anthropology" | and "sociology". Without some feedback loop keeping them | honest, why would I expect anthropologists or sociologists | to tell me a true story about why someone believes what | they do, any more than that person or anyone else? In | aerospace engineering, the feedback loop is that if your | design is bad, your jet engine won't work. As a result, I | generally trust aerospace engineers about jet engines. But | what is there to stop sociologists, anthropologists, etc | from just settling on some bullshit that agrees with their | preconceived beliefs or flatters their group status and | promoting it forever? | | But back to math. The history of mathematical ideas is | complicated and interesting, but it isn't really that | relevant to the question of whether the things those ideas | are _about_ are "real", which is equivalent to asking | whether mathematical platonism is true or not. The question | of platonism comes down to the definition of words like | "real" and "exist". It is very easy to equivocate using | these words, which is why most discussions about | mathematical platonism are so low quality. I think the | overall question isn't that meaningful so I'm not really a | platonist or an anti-platonist. In most parts of human | life, when I say "x exists", I mean that I can reach out | and touch x, that it has a mass, temperature, surface | texture, etc. In math, when I say "x exists" I just mean | that I can talk about x without creating any logical | contradictions. The square root of -1 may not exist in the | same sense as my laptop here, but it exists in the sense | that I can do things with it, such as add, multiply, raise | to powers, etc, without reaching a contradiction in my | formal system. So the whole "out there" thing doesn't | really matter. There doesn't need to be an "out there" in | order for me to meaningfully say that the square root of -1 | exists. | | I think that a lot of philosophy is like this too, when you | mentally zoom in really closely on a problem, it often | reduces to some kind of equivocation or inconsistent | language usage. | | Btw I don't really consider anthropology or sociology to be | real intellectual disciplines, and I'm pretty on the fence | about psychology and economics. I realize that is an | unpopular opinion but I've thought about it a lot and I'm | pretty certain that it's correct. Aerospace engineering is | real because it _attaches_ to some fundamental reality, | namely that of the spinning fan blades, the combusting | fuel, etc. If you get your engineering wrong, the fan | blades won 't spin. Likewise, math is attached to systems | of axioms. When your do your math wrong, you get a | contradiction. Sociology and anthropology don't attach to | anything, they're like a closed loop, like theology. If you | get your anthropology wrong, nothing really happens. | nathias wrote: | No it isn't scientifically supported because science does not | include ontology and episemology as its domain. I'm not a | platonist, but the reasons for not being platonists are | philosophical. | dandanua wrote: | > there's no god "behind the curtain" | | have you looked there already? :) | mjburgess wrote: | This view isnt "scientifically supported" because science is | neutral on (indeed, even presupposes) the existence of abstract | objects. | | No one believes abstracta have a physical location -- they lack | physical properties. The claim "2 + 2 = 4" is true -- and | clearly not true invirute of anything anyone thinks... if we | kill that person (/people), it is no less true. | | Indeed, if numbers don't exist (for example), do we suppose | that we can't communicate issues of quantity with other species | (, & possible alien life, etc. etc.) ? (If we can, what shared | things are we talking about when we quantify?) | | It seems deeply implausible to say that our use of number is | circumstantially psychological -- any description of reality is | going to be indispensably quantitative --- quantity _is_ what | we are talkng _about_. We are not talking about ourselves. | echopurity wrote: | jhedwards wrote: | I've thought about this problem quite a bit and, while my | initial position was the same as above (math is not "real" | per se) I had to concede that integers are real, because | quantity is self-evidently real. | | If you have four oranges, the quantity "four" is right there. | If you take away one of those oranges you know that the | result cannot be split evenly without a remaining orange | because of the properties of odd numbers. | | If you cut the remaining orange in half then you get a | rational number, but is that self-evidently real? The halves | of the orange are only "halves" because we consider them in | relation to their origin, which we consider to be "one" | orange. So rational numbers necessarily involve the human | action of relating some quantity to a reference quantity, | therefore they are a higher-level abstraction built on top of | the fundamental physical property of quantity. | | In the end I decided that math is based on a foundation of | quantity (and maybe "space" as well?) and everything else was | a derived abstraction. I am very curious if anyone else has a | good argument for other parts of math being fundamental. | viovanov wrote: | Does four really exist as 4? Maybe it's just 2 squared. | dagw wrote: | _integers are real, because quantity is self-evidently | real._ | | But the there are more integers than there are quantifiable | 'things'[1]. Are integers that are a lot larger than, say | the size of the power set of all fundamental particles in | the universe still "self-evidently real". | | [1] Assuming a finite universe (or a finite number of | finite universes) and a few other things. | ajuc wrote: | Electromagnetic field changes are described by complex | numbers. So not only you need fractions, you need | irrational numbers and imaginary numbers to describe the | universe. Why is counting oranges "self-evidently real" and | describing electrons "kinda real"? | | I'd argue the opposite - oranges never appear in the laws | of physics. They are just our description of a collection | of atoms sharing some pretty loosely-defined | characteristic. Oranges aren't perfectly equivalent to each | another, so whether you count 1 small and 1 big orange as 2 | or 1.5 oranges depends on your arbitrary decision. How | about 1 orange and 1 hybrid species between orange and | grapefruit? How close you need to be to be considered | orange? Classes of equivalence are determined by us not by | the universe, and numbers are derived from that. | | Electrons on the other hand are as undeniably real as | anything in this universe can be. | jhedwards wrote: | Quantity has real concrete measurable effects that exist | irrespective of the philosophical problem of | classification. If I have two acorns I know I can | potentially grow two very real trees. They are countable | and that directly relates to the effect they can have on | the world. I like to think that maybe every tree is one | tree, or that all trees are part of a unity of "plants", | but practically speaking seeds and trees are countable | entities no matter how I classify them. | | If there are two planets, we can discuss philosophically | that one might be a "moon" and not a "planet", or in some | sense that the planet is "continuous" with the space dust | or whatever. But the existence of two distinct bodies in | space will still create very specific gravitational | fields from their interactions. Tides are different if | you have one vs two moon, Lagrange points etc. | | As for electromagnetic fields, I am not smart enough to | make a judgement on that. They are described by complex | numbers, but does that mean they reflect a physical | embodiment of complex numbers? Or is it just that we | require complex numbers in order to resolve their | behavior into something measurable? I love to learn about | electricity but sadly the math is beyond my ability. | pdonis wrote: | _> Electromagnetic field changes are described by complex | numbers._ | | You can do this, but there's no need to. You can describe | electromagnetism using only real numbers. | | A better argument for imaginary numbers being necessary | to describe the universe is quantum mechanics, since | quantum interference (in particular destructive | interference) means that two possible events that each | have a positive probability taken in isolation can cancel | each other out, implying that probabilities can combine | with a minus sign. And that means that probability | amplitudes, which are square roots of probabilities, can | have nonzero imaginary parts. | mettamage wrote: | 4 oranges are real because we have the neural architecture | to classify the oranges as belonging to the same group | according to whatever our classification criteria are. | | What if you can't classify but only be conscious of input? | Kinda like being in a super dreamy state (or psychedelic | one). From that state of consciousness, numbers aren't real | but reality can be (in the psychedelic case). | | Just brainstorming | darkscape wrote: | > I am very curious if anyone else has a good argument for | other parts of math being fundamental. | | Groups. You can stay in your kitchen (the neutral element) | or go into the bedroom, then come back (inverses). In my | mind, this is as real as quantity. | hansbo wrote: | But even if you deep dive enough, there are discrete values, | like in Quantum Mechanics. And as long as you have discrete | values, you have integers, no? So integers do not seem only | like human models, they seem to me as something innate in the | universe. | helen___keller wrote: | Quantum mechanics is a mathematical description of the | behavior of the universe, so wouldn't invoking this to prove | mathematical objects exist be begging the question? | | Not to say I agree with GP, but I don't think it will be so | easy to prove GP wrong either | dTal wrote: | "Discrete values" are also a human metaphor. You say there | are two apples on your desk? I say there is a fuzzy quantum | mess of probability distribution functions on your desk. "Two | apples" is in your mind. | nh23423fefe wrote: | and spin? | shusaku wrote: | I'm baffled that you're invoking QUANTum mechanics to | ascertain that discrete values don't exist. At any rate, | nominalism has a rich history, so I doubt these hacker news | comments will solve the issue... | igorkraw wrote: | are atoms discrete? we used to think so. we might never get a | better model than quantum physics and it might still be wrong | and fail to explain things. So there is a human idea of | "discrete element" that we used to apply to everything - and | as we look closer, it always breaks down. that doesn't mean | it's a useless abstraction, but it is am abstraction - a tool | for thought, a map, not the territory | andreareina wrote: | Science has nothing to do with it, rather it's a question of | philosophy and what we define as being real. | dTal wrote: | Science is "what we have evidence for". Is there evidence for | some abstract mathematics that we didn't invent? | throwaway17_17 wrote: | I agree that this view it is not popular, but I also do not | think that supporters often articulate their view/support well. | I am a hard materialist and the amount of platonic-leaning | discourse around the fundamentals of mathematics confuses me. I | do not know how so many people (typical those outside | philosophy and mathematical foundations) just assume a platonic | style view. | dTal wrote: | I am currently reading "Where Mathematics Comes From" by | George Lakoff and Rafael E. Nunez - the same Lakoff who | authored the seminal "Metaphors We Live By", so I have a lot | of time for him. At first it seems like they're just going to | explore the pedagogical psychology of mathematics - how | interesting! But then right at the end of the preface they | hit you with "and by the way this is all there is to it, | mathematical Platonism is a lie", which struck me immediately | as straying out of their lane. But it seems their | investigation into the titular question overwhelmingly led | them to this conclusion. The argument is pretty simple - if | there is a "platonic mathematics", we cannot have any direct | experience of it. All mathematical thought, like all thought | in general, is metaphorical. The predictive power of | mathematics in the real world is unsurprising because we | throw away the metaphors that don't work well. | | I do not _like_ this conclusion. Mathematics has always been | something of a religion for me. But I can find no flaw with | the argument. From a scientific perspective, mathematics | bottoms out at "what goes on in human noggins". | imbnwa wrote: | >The argument is pretty simple - if there is a "platonic | mathematics", we cannot have any direct experience of it. | | Aside, but this is also Aristotle's exact argument against | Platonism in general, though when he makes it in the | Nichomachean Ethics he is specifically talking about | ethical Good (if the definition/actual taking place of the | Good lies in some other plane, we can't participate in it | so no one is or can be good), but the idea is the same even | when he's talking about what a soul is in De Anima. | Aristotle doesn't believe in 'souls' in the way we think of | them as religio-spiritual entities that exceed the capacity | of the body; a 'soul' for Aristotle _is_ the body but in a | way that radically challenges the idea of a body as mere | shell or vessel - soul is what any form of life repeats | doing, as a body, in order to continue being itself. It | should be noted that a lot of time at Aristotle 's Academy | was spent in Zoology, studying animals and their anatomy. | darkscape wrote: | I'll have to read the book, but in my mind, the (emprical) | study of humans and their brains doesn't shed light on the | metaphysical question of the nature of mathematics. What | they find is how humans have developed to do mathematics. | We could have evolved to be the way we are with or without | mathematics being "out there". Survival in the physical | world would lead us to "throw away the metaphors that don't | work well". At any point in time a concrete human being | would still be able to consider only a limited set of | mathematical ideas i.e. for humans "mathematics bottoms out | at "what goes on in human noggins"". | | I'd say the patterns you mentioned in an earlier comment | are a way for math (or parts of it e.g. some integers) to | be "out there". If humans embody mathematics, then | analogously so do those patterns. | mannykannot wrote: | I don't think the issue has been as definitively settled as | you have been persuaded to think. Let's take a look at the | claim "if there is a 'platonic mathematics', we cannot have | any direct experience of it" (I realize this is probably a | paraphrase of a fuller argument, but it is what I have to | work with here.) | | Firstly, note the word "direct" here. If it has any | relevance, then the authors have assumed the burden of | explaining either that there are only direct experiences, | or why indirect experiences don't count. | | Secondly, what are the premises here? If this is supposed | to be axiomatic, then there is literally no reason to | either accept or reject it, and claims that the issue has | been settled are just statements of belief; otherwise, the | argument needs to have premises that are not begging the | question in some way. As it stands, this claim is not an | argument; it is more of an intuition pump. | | Metaphysical discussions tend to (always?) end up as being | about the meaning of words like 'real' and 'true'. Whether | such discussions can really tell us anything about what | must be true is arguably the most meta question in | metaphysics. | tim333 wrote: | >all numbers are imaginary.... mathematics is an accumulated | edifice of metaphors designed by human brains | | Or you can say they exist but in a different way to physical | reality. | | I mean pi probably still was 3.14159... before humans evolved | so it's not our fault really. | | Personally I think maths not only exists but physical reality | is a subset. I mean why else is there something rather than | nothing? Scientifically it's the only hypothesis that works for | that really. | mannykannot wrote: | > But it is the only scientifically supported one. | | Really? What is the empirical evidence for it? | canjobear wrote: | Reality is that which, when you stop believing in it, doesn't | go away. -Philip K Dick | | Even if you stop "believing in" math, your proofs are still | either correct or incorrect. | dagw wrote: | The proofs are only correct in as far as you believe in the | Axioms of mathematics that those proofs are built on. Stop | "believing in" the axioms and the proofs are no longer true | or even meaningful. | canjobear wrote: | But it is still the case that IF the axioms hold, THEN the | proofs are either valid or not. | marcosdumay wrote: | So it's conditional reality. Now make that fit within | your usual realistic philosophy... | canjobear wrote: | Easy. There exist contingency relationships between | axioms and theorems provable from those axioms. | marcosdumay wrote: | Oh, yeas, your proof is quite real. And it's completely | meaningless, being all about imaginary things. | | It can only have any meaning if you adhere to some | scientific model. | | At this point you've deviated so much from the OP | discussion that you could as well talk about angels | dancing in pinheads. Any quantification of them is as | real as your proof. | tasha0663 wrote: | You can boil down pretty much everything to "an accumulated | edifice of metaphors designed by human brains, for human | brains". | | In the game Hearts, if you take most of the spades you lose. | However, if you manage to take _all the spades_ you win, and | they call it "shooting the moon". | | In a similar fashion, when you reject everything as an unreal | system of metaphors, Platonism "shoots the moon" by having us | reexamine what we thought we meant by "real" in the first | place. | rthomas6 wrote: | What finally made imaginary numbers intuitively make sense to me | is realizing that the number i just represents a 90 degree | rotation on the complex plane. That's why i*i = -1 (it's rotating | 180 degrees), why imaginary numbers are orthogonal to real | numbers, why e^ix = cos(x) + i*sin(x) makes sense, everything. | | When you are dealing with 2 dimensions, complex numbers are a | kind of hack for representing both dimensions without any kind of | vectors or pairs or anything, just numbers. | polotics wrote: | Mathematicians have always sucked at naming their variables, and | constants, and types... This has given pundits of all ilk | countless opportunity to debate... ___________________________________________________________________ (page generated 2022-02-10 23:00 UTC)