The previous chapter argued in detail that the Priestly source represents a deliberate break with conventional ancient Near Eastern views of disease. Before we can explore the broader significance of this break, it is necessary to first address the more fundamental issue of how notions of causation originate both in the psychological development of individuals (ontogeny) and on the scale of cultures. This framework will provide a basis for situating the Priestly views of disease and pollution in comparison to similar discursive developments outside of ancient Israel, providing an opportunity to test the plausibility of the hypothesis proposed in the previous chapters regarding the polemical tendencies in the Priestly source.