How were the commandments in Animal Farm broken?

Almost immediately after the Commandments are written the cows have to be milked. The milk they produce is taken by the pigs exclusively so the seventh Commandment seems to be undermined from the very beginning. When the pigs also start claiming the windfall Apples, Squealer explains that they are not taking them as privilege but because science has shown that milk and Apples are necessary for the pigs' "brain work". This at least satisfies the animals that they are equal to the pigs but it does not fool the reader.

The first two Commandments are subtly broken in the first years of Animal Farm but there is no attempt to rewrite them. Snowball, the hero of the Battle of the Cowshed, becomes an enemy of the farm after his expulsion by Napoleon, while the resumption of trade via Mr Whymper causes some discussion but, as Squealer points out, trade was not banned in writing and Mr Whymper is not treated as a friend.

The first alteration to the Commandments comes after the pigs move back into the farmhouse. The ban on sleeping in beds is changed in Napoleon's favour by the addition of the Words "with sheets". At this point in the history of the farm the pigs do not quite have enough power to do what they like and Squealer is forced to change the Commandments to fit new circumstances. But sleeping in beds is a minor matter compared to murder, and the next alteration to the Commandments is far more shocking. After the failures of the winter and the collapse of the first windmill, the pigs use Snowball as scapegoat. This leads to the 'show trials' in which animals 'confess' to crimes inspired by Snowball. The horrific executions that follow are in direct contradiction of the original sixth Commandment but when this is checked the Words "without cause" have been added.

Napoleon's selfish behaviour is the cause of the alteration to the fifth Commandment. When he and the other pigs get drunk, Napoleon's hangover is a cause for alarm but all that eventually happens is that the Words "to excess" are added to the Commandment. It is at this point that Squealer's part in the changes to the Commandments is revealed to the reader as he falls off the ladder he was using to reach the barn wall. After this incident, more and more of the farm's resources are diverted to the provision of alcohol for the pigs. The sale of Boxer's body to the knackers results in the delivery of a crate of fine food and alcohol.

No minor alteration is ever made to the third Commandment about wearing clothes. This is because by the time the pigs adopt clothes they are so powerful, and the other animals are so fearful, that it is unnecessary. Instead, all pretence of "unalterable laws" is abandoned and the Commandments are replaced by the meaningless slogan

"All animals are equal, but some are more equal than others."