At the foot of the end wall of the big barn, where the Seven Commandments were written, there lay a ladder broken in two pieces. Squealer, temporarily stunned, was sprawling beside it, and near at hand there lay a lantern, a paint-brush, and an overturned pot of white paint. The dogs immediately made a ring round Squealer, and escorted him back to the farmhouse as soon as he was able to walk. None of the animals could form any idea as to what this meant, except old Benjamin, who nodded his muzzle with a knowing air, and seemed to understand, but would say nothing.

George Orwell

Animal Farm. Chapter 8. It is clear from this episode that Squealer has been changing the Seven Commandments. Evidence of the corruption in Napoleon’s and his second-in-command Squealer’s leadership. Benjamin, the long-lived donkey, is the only one who has figured this out.