According to Sowa (2000),[5] up until the twentieth century, three assumptions described by Max Born in 1949 were dominant in the definition of causality:
"Causality postulates that there are laws by which the occurrence of an entity B of a certain class depends on the occurrence of an entity A of another class, where the word entity means any physical object, phenomenon, situation, or event. A is called the cause, B the effect.
"Antecedence postulates that the cause must be prior to, or at least simultaneous with, the effect.
"Contiguity postulates that cause and effect must be in spatial contact or connected by a chain of intermediate things in contact." (Born, 1949, as cited in Sowa, 2000)