A paragraph in the book about abolishing money is similar to a paragraph in Frederick Engels' "Principles of Communism". Gaddafi wrote: "The final step is when the new socialist society reaches the stage where profit and money disappear. It is through transforming society into a fully productive society, and through reaching in production a level where the material needs of the members of society are satisfied. On that final stage, profit will automatically disappear and there will be no need for money."