Eat the Rich - A Treatise on Economics Author:P.J. O'Rourke You buy stock because you think other people will think this stock is worth more later than you think it's worth now. Economists call this - in a rare example of comprehensible economist terminology - the "Greater Fool Theory". Speaking of folly, you can also invest in the commodities market. This is where you buy thousands of pork bellies and s... more »till don't know what you're going to have for dinner because, in the first place, you're broke from fooling around in the commodoties market and, in the second place, you're not completely insane. You didn't actually have those pork bellies delivered to your home. What you did was buy a "futures contract" from a person who promises to provide you with pork bellies in a couple of months if you pay him for the pork bellies today. You did this because you think pork belly prices will rise and you'll be able to resell the delivery contract and make out like a ...perhaps "make out like a pig" is not the appropriate simile in this case. Of course, if prices fall, you've still got the pork bellies, and won't your spouse be surprised?