Occam’s razor

You know the Occam’s razor principle, don’t you?  Nowadays it’s boiled down to mean that, if you’ve got a simple answer, you often don’t need to look for something more complex.  At medical school, students who are all excited about rare diseases they’ve read about in books often need to be reminded to look for a straightforward diagnosis.  They’re told, “If you hear hoofbeats outside the window, assume it’s a horse, not a zebra.”  I thought of this when I read Chris Muir’s stellar Day by Day cartoon (which, sadly, I can’t figure out how to run as a daily cartoon in WordPress):

Hat tip:  Little Green Footballs