{"id":12023,"date":"2013-04-21T18:19:59","date_gmt":"2013-04-21T23:19:59","guid":{"rendered":"http:\/\/blog.kenperlin.com\/?p=12023"},"modified":"2013-04-21T22:39:11","modified_gmt":"2013-04-22T03:39:11","slug":"defending-the-second-dimension","status":"publish","type":"post","link":"http:\/\/blog.kenperlin.com\/?p=12023","title":{"rendered":"Defending the second dimension"},"content":{"rendered":"<p>Let&#8217;s say our two dimensional creature is named Ariel (which sounds like &#8220;area&#8221;) and our one dimensional being is named &#8220;Lenny&#8221; (which sounds like &#8220;length&#8221;).<\/p>\n<p>Let&#8217;s also assume that Lenny can detect color as well as something equivalent to what we might call &#8220;thickness&#8221; &#8212; which might appear to him as a more vivid color, or some sort of texture, or perhaps a greater visual density.<\/p>\n<p>When Ariel wants to show various shapes to Lenny, she can use both thickness and color to suggest a second dimension.<\/p>\n<p>For example, suppose Ariel wants to convey the idea of &#8220;a square&#8221; or &#8220;a diamond&#8221;.  To us these are rotated versions of the same shape, but to Lenny, rotation is a very advanced concept indeed, so Ariel will present them as different shapes.<\/p>\n<p>Lenny can see only an &#8220;x&#8221; dimension, but Ariel asks him to imagine an extra &#8220;y&#8221; dimension.  Ariel uses both &#8220;redder&#8221; and &#8220;thicker&#8221; to convey &#8220;nearer in y&#8221;, and &#8220;bluer&#8221; and &#8220;thinner&#8221; to convey &#8220;further away in y&#8221;.   Of course to Lenny these are just abstractions &#8212; but Lenny understands them because he already has experience with &#8220;near&#8221; and &#8220;far&#8221; along his own x dimension.<\/p>\n<p>Below are a square (top) and a diamond (bottom).  In each case, on the left is what Ariel sees, and on the right is what she draws for Lenny (the gray arrows show Ariel&#8217;s idea of the correct viewing direction for each shape):<\/p>\n<p><center><img decoding=\"async\" src=\"http:\/\/blog.kenperlin.com\/wp-content\/uploads\/2013\/04\/square-and-diamond.png\"><\/center><\/p>\n<p>Lenny discovers that he can use his powers of imagination to understand these two shapes, which makes him feel rather clever.<\/p>\n<p>But then Ariel tells Lenny that the square and diamond are actually the same shape &#8212; each is just a rotated view of the other.<\/p>\n<p>As you might imagine, Lenny finds this very challenging.  After all, he has no experience at all with the concept of rotation.  &#8220;Oh dear,&#8221; he tells her, &#8220;I&#8217;m afraid this is going to require some non-linear thinking.&#8221;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Let&#8217;s say our two dimensional creature is named Ariel (which sounds like &#8220;area&#8221;) and our one dimensional being is named &#8220;Lenny&#8221; (which sounds like &#8220;length&#8221;). Let&#8217;s also assume that Lenny can detect color as well as something equivalent to what we might call &#8220;thickness&#8221; &#8212; which might appear to him as a more vivid color, &hellip; <a href=\"http:\/\/blog.kenperlin.com\/?p=12023\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Defending the second dimension&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"_links":{"self":[{"href":"http:\/\/blog.kenperlin.com\/index.php?rest_route=\/wp\/v2\/posts\/12023"}],"collection":[{"href":"http:\/\/blog.kenperlin.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/blog.kenperlin.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/blog.kenperlin.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/blog.kenperlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=12023"}],"version-history":[{"count":25,"href":"http:\/\/blog.kenperlin.com\/index.php?rest_route=\/wp\/v2\/posts\/12023\/revisions"}],"predecessor-version":[{"id":12049,"href":"http:\/\/blog.kenperlin.com\/index.php?rest_route=\/wp\/v2\/posts\/12023\/revisions\/12049"}],"wp:attachment":[{"href":"http:\/\/blog.kenperlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=12023"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/blog.kenperlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=12023"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/blog.kenperlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=12023"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}