Table 1.

Somatic mutation theory.

Cancer is a disease of genetic mutation. Cancer is derived from a single somatic cell. The initiation process, and therefore, the process of carcinogenesis, is irreversible. The default state of a cell is quiescence. Adjacent tissue has only a supporting role in carcinogenesis. A reductionism philosophy: the properties of the whole can be inferred, deduced, calculated, and predicted from the properties of the parts. Phenomena occurring at one level (cancer at tissue level) can be explained by understanding the properties at a lower level (molecular and chemical properties at the cellular level). There is unidirectional upward causation.