My grandfather continues to send me flong. I've discarded the latest but I see that copies of it are online in various places (including a debunking by Snopes).
[a bunch of stuff snipped]Here's the idea:
For the rest of this year, DON"T purchase ANY gasoline from the two biggest companies (which now are one), EXXON and MOBIL. If they are not selling any gas, they will be inclined to reduce their prices. If they reduce their prices, the other companies will have to follow suit.
[lots more snippery]
This was brought to mind while I stopped to get gas while driving to Massachusetts today, and I turned it over in my head a little to figure out why I didn't buy the argument (apart from the fact that it appeared in a piece of flong). Before long I noticed that the same reasoning could be used to prove the opposite result:
For the rest of the year if you don't purchase ANY gasoline from EXXON and MOBIL, then other companies will be selling more gas and will be inclined to raise their prices. If they raise their prices, then EXXON and MOBIL will have no reason not to follow suit.
You shouldn't generally be able to prove a statement and its opposite using the same argument, so the argument must be flawed. Q.E.D.
I am geek.