A theory that states that any beverage (I.E. a liquid you drink) that comes packaged in a Green Bottle mixes well with anything else that comes in a Green Bottle.
Examples of things that come in Green Bottles
Sodas such as Mellow Yellow, Squirt, Sprite, Mountain Dew, and 7-Up.
Alcoholic beverages the comes in green bottles such as Heineken, Tanqueray, Midori, Hard Ciders, some Wine, and Jagermeister.
Other things such as NyQuil, some Teas, and other such things
Green Bottle Theory