In George Orwell's novel Animal Farm, the animals of the farm rebel against Mr. Jones. After taking over the Manor Farm, the animals (led by Snowball and Napoleon) begin to make the laws which the animals are expected follow. The original Seven Commandments of the Animal Farm are:
1. Whatever goes upon two legs is an enemy.
2. Whatever goes upon four legs, or has wings, is a friend.
3. No animal shall wear clothes.
4. No animal shall sleep in a bed.
5. No animal shall drink alcohol.
6. No animal shall kill any other animal.
7. All animals are equal.
Unfortunately for Snowball and Napoleon, many of the animals are illiterate (meaning that they do not know how to read). Therefore, the commandments become somewhat of a challenge for them to uphold.
Snowball, realizing that the commandments have become hard for other animals to read (let alone memorize), decides that the rules of the farm need to be changed. Snowball, realizing that one idea is, by far, most important, decides to eliminate all of the original commandments. The new, and more easily memorable, commandment is "four legs good, two legs bad."