These are the original commandments:
- Whatever goes upon two legs is an enemy.
- Whatever goes upon four legs, or has wings, is a friend.
- No animal shall wear clothes.
- No animal shall sleep in a bed.
- No animal shall drink alcohol.
- No animal shall kill any other animal.
- All animals are equal.
Some of the animals read poorly and some could not read at all. So, for some "four legs good, two legs bad" was used to sum up the commandments. This makes it easier for the pigs to change them.
As the pigs grow more powerful, especially after Snowball is chased off of the farm, Napoleon has Squealer change the commandments. For instance, in Chapter 6, the pigs start sleeping in beds. When Clover asks Muriel about this, Squealer claims that the 4th commandment had always been "No animal shall sleep in a bed with sheets." In Chapter 8, after Napoleon has some animals executed for opposing him, Squealer secretly changes the 6th commandment to "No animal shall kill any other animal without cause." Napoleon has Squealer secretly change the commandments so that they represent the pigs' new policy. And each time, the change is caused by an increase in the pigs' power and means a more oppressive life for the other animals.
At the end of Chapter 8, the animals find Squealer on the ground with a broken ladder, some paint, and a lantern. Afterwards, they notice another commandment they assume they had remembered incorrectly. Squealer had changed the 5th commandment to "No animal shall drink alcohol to excess." The final and most dramatic change is that the commandments are condensed to one: "All animals are equal. But some animals are more equal than others."