A revolution as defined by Wallace and adopted by Lubbock is a change of regime, or rules. If man was the new rule-setter through culture then the initiation of each of Lubbock's four periods might be regarded as a change of rules and therefore as a distinct revolution, and so "Chambers's Journal", a reference work, in 1879 portrayed each of them as:...an advance in knowledge and civilization which amounted to a revolution in the then existing manners and customs of the world.