Snip!t from collection of Alan Dix

<div class="parbase image slate_image section"><figure class="image inline left" style="width: 590px; "><a href="http://www.americanscientist.org/issues/feature/2002/3/why-we-see-what-we-do/3" target="_blank"><img title="greysquares_illusion" alt="optical illusion" src="/content/dam/slate/blogs/bad_astronomy/2013/12/06/greysquares_illusion.jpg.CROP.original-original.jpg"></a> <figcaption class="caption">Which lozenge is darker: The one on top, or the one on bottom?</figcaption> <p class="credit">Illustration by Dale Purves, used by permission</p> </figure> <script> requirejs(["jquery"], function($) { if ($(window).width() < 640) { $(".slate_image figure").width("100%"); } }); </script> </div> <div class="text parbase section"> <p>What&#x2019;s the illusion, you ask? Those two vertical lozenge-shapes are the same shade!</p></div>