No life worth naming ever comes to good <br />If always nourished on the selfsame food; <br />The creeping mite may live so if he please, <br />And feed on Stilton till he turns to cheese, <br />But cool Magendie proves beyond a doubt, <br />If mammals try it, that their eyes drop out. <br /> <br />No reasoning natures find it safe to feed, <br />For their sole diet, on a single creed; <br />It spoils their eyeballs while it spares their tongues, <br />And starves the heart to feed the noisy lungs. <br /> <br />When the first larvae on the elm are seen, <br />The crawling wretches, like its leaves, are green; <br />Ere chill October shakes the latest down, <br />They, like the foliage, change their tint to brown; <br />On the blue flower a bluer flower you spy, <br />You stretch to pluck it--'tis a butterfly; <br />The flattened tree-toads so resemble bark, <br />They're hard to find as Ethiops in the dark; <br />The woodcock, stiffening to fictitious mud, <br />Cheats the young sportsman thirsting for his blood; <br />So by long living on a single lie, <br />Nay, on one truth, will creatures get its dye; <br />Red, yellow, green, they take their subject's hue,-- <br />Except when squabbling turns them black and blue!<br /><br />Oliver Wendell Holmes<br /><br />http://www.poemhunter.com/poem/the-mind-s-diet/
