Laziness and foolishness are inextricably linked according to Solomon’s verse today:

Ecc 10:15  The toil of a fool so wearies him that he does not even know how to go to a city.

Work is so worrisome for the fool that he can’t even find something as obvious as a city.  

Isaac Newton’s law of motion comes to mind here….an object is motion wishes to stay in motion while an object at rest wishes to stay at rest.  Now that specifically talks about the laws of inertia and gravity, but it is certainly applicable to people who work versus people who choose to loaf.  

A loafer will find any excuse not to work, too sick, too tired etc.  Meanwhile, someone who who stays busy is typically the one you can rely on, versus the shiftless fool who isn’t asked to work or do anything.  Solomon declares that the lazy person and the fool share commonalities.