My suggestion at the end of the previous chapter was that in order to fully understand the dynamics of law, we must switch between two models. We need the product model in order to identify how legal doctrine develops over time. If we want to know precisely what changes, then the simplifying model of law as a product is essential; we must be able to describe the legal norms that were valid in, for example, the year 2000, and then see how the legal doctrine has developed since then. However, in order to understand why this has changed and what the underlying trends are, we need to move to the practice model. Only then can we fully apprehend the underlying dynamics, the ambiguities and developments in legal understandings, the emergence of new patterns of interaction, and the gradual adaptation in interaction to changing circumstances and changing convictions.