{"id":713,"date":"2008-12-10T15:11:31","date_gmt":"2008-12-10T15:11:31","guid":{"rendered":"http:\/\/scientopia.org\/blogs\/goodmath\/2008\/12\/10\/why-math\/"},"modified":"2008-12-10T15:11:31","modified_gmt":"2008-12-10T15:11:31","slug":"why-math","status":"publish","type":"post","link":"http:\/\/www.goodmath.org\/blog\/2008\/12\/10\/why-math\/","title":{"rendered":"Why Math?"},"content":{"rendered":"<p><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" alt=\"bump-graph.gif\" src=\"https:\/\/i0.wp.com\/scientopia.org\/img-archive\/goodmath\/img_343.gif?resize=183%2C136\" width=\"183\" height=\"136\" class=\"inset right\" \/><\/p>\n<p> So, why math?<\/p>\n<p> The short version of the answer is remarkably simple: math provides<br \/>\na tool where you can, without ambiguity, prove that something is true or false.<\/p>\n<p> I&#8217;ll get back to that &#8211; but first, I&#8217;m going to make a quick diversion, to help you understand my basic viewpoint on things.<\/p>\n<p> This blog actually started in response to something specific. I was reading<br \/>\n<a href=\"http:\/\/scienceblogs.com\/insolence\">Orac&#8217;s blog &#8220;Respectful Insolence&#8221;<\/a>, and<br \/>\nhe was fisking a study published by the Geiers, purporting to show a change in the trend in autism diagnoses. Orac was attacking it on multiple bases, but it struck me<br \/>\nthat the most obvious problem with it was that it was, basically, a mathematical argument, but the math was blatantly wrong. It was making a classic statistical analysis mistake which is covered in first-year statistics courses. (And I mean<br \/>\nthat very literally: when I was in college, I lazily satisfied some course requirements by taking a statistics course given by the Poly Sci department, and<br \/>\nin statistics for political scientists, they covered exactly the error made by the Geiers in November of the fall semester.) It struck me that while there were a lot of really great science bloggers &#8211; people like Orac, PZ Myers, Tara Smith, and so on &#8211; that I didn&#8217;t know of anyone doing the same thing with math.<\/p>\n<p> So I <a href=\"http:\/\/goodmath.blogspot.com\/2006\/03\/bad-math.html\">started this blog on Blogger<\/a>. And my goals for the blog have never changed. What<br \/>\nI&#8217;ve wanted to do all along is:<\/p>\n<ol>\n<li> To show people the beauty of math. Math is really wonderful. It&#8217;s<br \/>\nfun, it&#8217;s beautiful, it&#8217;s useful. But people are <em>taught<\/em> from<br \/>\nan early age that it&#8217;s useless, hard, and miserable. I want to show<br \/>\notherwise, by describing the beauty of math in ways that are approachable<br \/>\nand understandable by non-mathematicians.<\/li>\n<li> To help people recognize when someone is trying to put something past<br \/>\nthem by abusing math &#8211; what I call obfuscatory mathematics. Because so many people don&#8217;t know math, hate it,<br \/>\nthink it&#8217;s incomprehensible, that makes it easy for dishonest people<br \/>\nto fool them. People throw together garbage in the context of a mathematical<br \/>\nargument, and use it to lend credibility to their arguments. By pointing<br \/>\nout the basic errors in these things, I try to help show people how to<br \/>\nrecognize when someone is try to use math to confuse them or trick them.<\/li>\n<li> To show people that they use and rely on math far more than they think.<br \/>\nThis relates back to the first point, but it&#8217;s important enough to<br \/>\njustify its own discussion. Lots of people believe that they can&#8217;t<br \/>\nunderstand math, and avoid it like the plague. But at the same time, they&#8217;re<br \/>\nusing it every day &#8211; they just don&#8217;t know it. My favorite example<br \/>\nof this is from my own family. My older brother had a string of truly horrible<br \/>\nmath teachers, and was convinced that he was horrible at math, couldn&#8217;t<br \/>\nunderstand it, couldn&#8217;t do it. You couldn&#8217;t even try to teach it to him,<br \/>\nbecause he was so sure that he couldn&#8217;t do it that he&#8217;d psych himself out<br \/>\nbefore he even started. But he&#8217;s a really smart guy. When he went to college,<br \/>\nhe studied music. I visited him at one point, and was watching him do an<br \/>\nassignment for his music theory course, where they were studying something<br \/>\ncalled serial composition. He was analyzing a musical score &#8211; and what<br \/>\nhe was doing to analyze it was taking determinants of matrices in mod-12<br \/>\narithmetic! Of course, he didn&#8217;t <em>know<\/em> that that was what he was<br \/>\ndoing; instead of the numbers 0 through 11, he was using the notes of the<br \/>\nmusical scale. But it was taking a determinant, just using a different<br \/>\nsymbol set. He had no trouble doing that; but try to teach him to compute<br \/>\na percentage, and he&#8217;ll insist not just that he can&#8217;t do it, but that<br \/>\nhe&#8217;s <em>incapable of learning to do it.<\/em> That kind of thing is<br \/>\nall too common &#8211; people do math every day, without knowing it. If they<br \/>\nunderstood whata they were doing, they might be open to learning more,<br \/>\nto being able to do more themselves &#8211; but because they&#8217;ve been taught<br \/>\nthat they can&#8217;t do it, they don&#8217;t see that they do.<\/li>\n<\/ol>\n<p> This will come around back to my basic point; keep reading below the fold.<\/p>\n<p><!--more--><\/p>\n<p> I really do honestly believe that<br \/>\nmath is absolutely fundamental to how we understand the world, and that<br \/>\nwhen we&#8217;re confronted with figuring out whether or not something is possible,<br \/>\nthe process that we use to determine it is, at its core, mathematical. Even<br \/>\nmore than that, I believe that it&#8217;s <em>impossible<\/em> to really understand<br \/>\nthings like machines and how they work without math. Math isn&#8217;t just important &#8211; it&#8217;s absolutely essential.<\/p>\n<p> When we look at something like the wind-powered vehicle that started this<br \/>\nwhole discussion, the way that we try to determine whether or not it works is,<br \/>\nfundamentally, a mathematical process. We build an abstract model of it in our mind, and use that model to analyze it and figure out if\/how it works. The only<br \/>\nconclusive way to figure out how\/if it works is, ultimately, to build<br \/>\na quantitative mathematical model, and figure out how the numbers add up.<\/li>\n<p> The reason that it&#8217;s always ultimately mathematical is because math &#8211; numbers and logic &#8211; is the only way to formulate a description of the thing that can actually<br \/>\nbe proven to be either correct or incorrect. Math provides the formalism that makes<br \/>\nit possible to say: &#8220;Yes, this works&#8221; in a way that can be checked by other people.<\/p>\n<p> Of course, just like it&#8217;s possible to screw up an informal mechanical description of something, it&#8217;s possible to screw up the mathematical model describing something, and get an incorrect result. But the critical difference is, in math, you can show<br \/>\nthat the model is wrong &#8211; and you can do it in an unmistakeable, undeniable way. That&#8217;s how I got convinced in this case &#8211; someone posted a mathematical argument<br \/>\nthat demonstrated how you could get power from the ground. And even though it went<br \/>\nstrongly against my own intuition &#8211; it was incontrovertible. I couldn&#8217;t find a problem with the math; and if there was no problem with the math, that meant that I had to be wrong. There&#8217;s no room for argument there &#8211; I had to either show where the math was wrong, or accept that it was right. Math allows you to form unambiguous<br \/>\nanalyses like that.<\/p>\n<p><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" alt=\"steorn.jpg\" src=\"https:\/\/i0.wp.com\/scientopia.org\/img-archive\/goodmath\/img_344.jpg?resize=250%2C187\" width=\"250\" height=\"187\" class=\"inset right\" \/><\/p>\n<p> To illustrate why I say math is really essential, it&#8217;s useful to think about some<br \/>\nexamples. As I&#8217;ve said, I&#8217;ve been around the net for a while, and I&#8217;ve been absolutely<br \/>\nbombarded by crackpots of all kinds. My favorites are the perpetual motion folks; it<br \/>\njust never ceases to amaze me how many of them there are, or how committed they are to<br \/>\nsomething that can&#8217;t possibly work. Ignoring the more sophisticated ones for the<br \/>\nmoment, there are still tons of people out there pushing variations on some of the<br \/>\noldest perpetual motion machines, like the old overbalanced wheel. Those are<br \/>\nbased on pure ignorance; we know that those things don&#8217;t know, and we know why. But there are people pushing much more sophisticated versions of the same basic idea &#8211; ranging from <a href=\"http:\/\/www.nottaughtinschools.com\/Yull-Brown\/index.html\">Brown&#8217;s Gas<\/a> to <a href=\"http:\/\/peswiki.com\/index.php\/Directory:Perendev_Power_Developments_Pty_(Ltd)\">magnetic motors<\/a>.<\/p>\n<p> Perpetual motion is impossible. We know that (or at least the sane among us know<br \/>\nthat). So obviously, none of the perpetual motion machines work. But that doesn&#8217;t stop<br \/>\ntheir inventors from <em>believing<\/em> that they work. There are plenty of scammers out there (<a href=\"http:\/\/www.steorn.com\/orbo\/\">Steorn<\/a> comes to mind) who know full well that they&#8217;re full of shit. But there are also a lot of genuinely honestly deluded folks who really, honestly believe that they&#8217;ve found something amazing, and really don&#8217;t understand that they&#8217;ve got it wrong.<\/p>\n<p> How do you refute one of these people? <\/p>\n<p> Let me take one example &#8211; <a href=\"http:\/\/www.nottaughtinschools.com\/Yull-Brown\/index.html\">Brown&#8217;s gas<\/a>. Brown&#8217;s gas is a name for a mixture<br \/>\nof hydrogen and oxygen, in perfect two-to-one atomic proportions. If you look around the web, you&#8217;ll find hundreds of people who really, sincerely believe that they<br \/>\ncan produce more energy by burning Brown&#8217;s gas than they consume producing it. <\/p>\n<p> In fact, they can even provide calorimetric measurements showing that<br \/>\nthe amount of energy coming from their burner is larger than the amount of electricity<br \/>\nthat it took to split the water into hydrogen and oxygen.<\/p>\n<p> The usual argument over this follows roughly the following form:<\/p>\n<ul>\n<li> Look! Brown&#8217;s gas provides clean free energy!<\/li>\n<li> No, that&#8217;s impossible.<\/li>\n<li> Yes, it does!<\/li>\n<li> No, it can&#8217;t. Burning hydrogen and oxygen produces an quantity of<br \/>\nenergy exactly equal to the amount of energy it takes to split the<br \/>\nwater molecule; and since you can&#8217;t extract all of the energy from burning it,<br \/>\nyou&#8217;re losing energy in the process.<\/li>\n<li> Yes, it does work! In perfect proportions, hydrogen and oxygen combust in<br \/>\nan implosive manner rather than an explosive one, and that gives us more<br \/>\nenergy than it took to split the water!<\/li>\n<li> No, it can&#8217;t.<\/li>\n<li> Yes, look, here&#8217;s some measurements!<\/li>\n<\/ul>\n<p> And so on. How can you possibly really refute them?<\/p>\n<p> You can argue &#8217;til you&#8217;re blue in the face, and the argument will just go around<br \/>\nin circles: &#8220;Yes it does&#8221;, &#8220;No it doesn&#8217;t&#8221;, forever. No informal argument will ever<br \/>\nproduce a conclusive result.<\/p>\n<p> But once you bring math into the discussion, you can force a conclusion. By<br \/>\nworking out the energy inputs and the energy outputs, and comparing them. That&#8217;s math.<br \/>\nIn the Brown&#8217;s gas case, in their measurements, the input energy is the amount of<br \/>\nelectricity that it took to split the water into hydrogen and oxygen; the output is<br \/>\nthe amount of energy they produced by burning them. But there&#8217;s a missing element in<br \/>\nthe equation: the burning measurements come from burning a mixture of<br \/>\n<em>compressed<\/em> hydrogen and oxygen. The burning fuel is coming out at a high<br \/>\nspeed even <em>before<\/em> combustion. In the &#8220;energy out&#8221; measurements, the<br \/>\nmeasurement includes energy coming from the decompression of the gases.<\/p>\n<p> Brown&#8217;s gas proponents will insist that the energy it took to compress the gas<br \/>\nwas less than the surplus they&#8217;re seeing from burning it. If you use direct<br \/>\nmeasurements, they&#8217;ll claim that it&#8217;s unfair, because of inefficiencies<br \/>\nin the compressor you measured, or problems with the valves on the compressed gas<br \/>\ncylinders, or any of a million other problems.<\/p>\n<p>  How can you prove them wrong?<\/p>\n<p> Math. You can compute the amount of energy <em>required<\/em> to split the water<br \/>\nand compress the gas in an ideal system, where the compressors and valves<br \/>\nand electrodes and such are all perfect and lossless. And still, the amount of energy<br \/>\nrequired in that perfect lossless system to split water and compress the resulting<br \/>\ngases will be <em>greater<\/em> that the amount of energy extracted by burning<br \/>\nthem.<\/p>\n<p> Without the mathematical argument, you can spend an endless amount of time trapped<br \/>\nin arguments about the specific compressor, the mechanics of combustion, and so on. Because for every &#8220;But that takes more energy&#8221;, they&#8217;ve got a comeback saying &#8220;No it doesn&#8217;t because &#8230;&#8221;. It isn&#8217;t until you reach the point of specific quantitative comparisons &#8211; that is, <em>mathematical<\/em> comparisons &#8211; that you get an unambiguous answer.<\/p>\n<p> When I make arguments in cases like this, one of the most common responses is<br \/>\nsomething along the lines of &#8220;But that doesn&#8217;t need math. My mechanical intuition<br \/>\nwould have convinced me of that without using any math!&#8221;, or &#8220;I don&#8217;t need math: a<br \/>\nworking demonstration is conclusive.&#8221; My response comes in two parts:<\/p>\n<ol>\n<li> Mechanical intuition is a fancy word for &#8220;doing math in your head&#8221;.<br \/>\nIt&#8217;s one of those examples I mentioned at the beginning of this<br \/>\narticle, where I said that people constantly do math without<br \/>\nknowing that it&#8217;s what they&#8217;re doing.  But when your mechanical<br \/>\nintuition tells you that the energy in a system can&#8217;t work, you&#8217;re<br \/>\nreally intuitively saying &#8220;It doesn&#8217;t add up&#8221;; that is, you&#8217;ve got<br \/>\nan intuitive sense of the math of the underlying system, and using<br \/>\nthat, you&#8217;re able to see that it doesn&#8217;t work. Even the terminology<br \/>\nthat&#8217;s commonly used in that situation reflects the underlying math:<br \/>\n&#8220;It doesn&#8217;t add up&#8221;.<\/li>\n<li> Mechanical intuition can be fooled, and the only way to conclusively show<br \/>\nthat the intuition wrong is mathematical analysis. The mechanical<br \/>\nintuition is based on an understanding of the mechanics and relationships<br \/>\nof the components of a system. If that understanding is wrong, you&#8217;ll get<br \/>\na wrong answer. How can you <em>prove<\/em> to someone that their<br \/>\nmechanical intuition is wrong? It comes back to some kind of<br \/>\nanalytical computation &#8211; i.e., math.<\/li>\n<li> Demonstrations are great, provided you really understand what&#8217;s being<br \/>\ndemonstrated. Just look around the net at the thousands and thousands of<br \/>\npeople who believe in magnetic free-energy engines! They&#8217;ve got<br \/>\ndemonstrations that really appear to work; they&#8217;ve got explanations that sound<br \/>\nincredibly convincing. But they&#8217;re <em>wrong<\/em> &#8211; because they&#8217;ve left<br \/>\nsome element out of the analysis. How can you really prove that?<br \/>\nMath: the inputs don&#8217;t match the outputs, and you can show that with<br \/>\nan analytical result.<\/li>\n<\/ol>\n<p> Once again, let me try another demonstration. You can create lots of<br \/>\ncart-like devices that work on treadmills.  You <em>can<\/em> produce<br \/>\na pairing of a torque-adjusting treadmill with a device to create the appearance<br \/>\nof the vehicle being accelerated by something other than the treadmill. That doesn&#8217;t mean that it really is. If you don&#8217;t know the mechanics of how the treadmill works,<br \/>\nthen putting your vehicle on the treadmill could triggering the treadmill to increase its motor output. If you don&#8217;t understand how your treadmill works, how can you be <em>sure<\/em> that it&#8217;s actually introducing energy to the system in a way you didn&#8217;t account for?<\/p>\n<p> An important thing to remember here is that math doesn&#8217;t have to be<br \/>\nsome gloriously complex system of equations. You don&#8217;t need to do<br \/>\na complete navier-stokes computation to show how a wing works. You don&#8217;t<br \/>\nneed to build molecular models of friction to describe a block sliding down<br \/>\na ramp. Math is just a framework for formal analysis; it&#8217;s the formal<br \/>\napplication of logic to provide a very precise description of something.<\/p>\n<p> Putting meters at various locations on a device and comparing the results<br \/>\n<em>is math<\/em>. One way of working around the problem that I suggested above with<br \/>\nmisunderstanding the operation of a treadmill would be to measure the energy being consumed by the treadmill. When you see that the energy consumed by the treadmill <em>increases<\/em> when a vehicle is placed on it, you&#8217;re observing that there&#8217;s<br \/>\nan unanticipated energy input to your system. To know if that&#8217;s really what&#8217;s producing your results, you need to compute how much influence that additional<br \/>\npower can produce. And as soon as you see the work &#8220;compute&#8221;, you&#8217;re in math-land.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>So, why math? The short version of the answer is remarkably simple: math provides a tool where you can, without ambiguity, prove that something is true or false. I&#8217;ll get back to that &#8211; but first, I&#8217;m going to make a quick diversion, to help you understand my basic viewpoint on things. This blog actually [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[24],"tags":[],"class_list":["post-713","post","type-post","status-publish","format-standard","hentry","category-goodmath"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/p4lzZS-bv","jetpack_sharing_enabled":true,"jetpack_likes_enabled":true,"_links":{"self":[{"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/posts\/713","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/comments?post=713"}],"version-history":[{"count":0,"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/posts\/713\/revisions"}],"wp:attachment":[{"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/media?parent=713"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/categories?post=713"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/tags?post=713"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}