Each strata had been then hierarchically subdivided. Social struggle also occurs within fields hierarchically nested under the economic antagonisms between social classes. Coggle produces hierarchically structured documents, like a branching tree. The system eventually developed into modern Linnaean taxonomy, a hierarchically organized biological classification. Rand argued that concepts are organized hierarchically. This introduction of presbyteries was somewhat revolutionary in the rather hierarchically structured Lutheran church. Dickson Mounds was a hierarchically organized society. The idea was that nature followed a "rule of five" with five groups nested hierarchically. He demonstrated that the human brain, while reasonably orderly was not organized hierarchically. It seems likely that they were organized hierarchically. Officers of both entities are hierarchically equal. There were few corporations treated hierarchically and strictly regulated. The courts are characterized by being specialist, regional, and hierarchically integrated at the federal level. This contrasts with other theorists who rank cities hierarchically. In this way a hierarchically ordered network of teachers may emerge.