The focus of expertise research is on exceptionally advanced performance
in professions that require long academic—and at least partly
scientific—education before entering into work. Surprisingly, only a few
studies have systematically examined the role of scientific thinking in
expertise development. Many studies have shown that initial scientific
knowledge seems to disappear during the course of expertise development.
This conclusion was challenged by the theory of encapsulation, which
describes how formal scientific knowledge is integrated with practical
knowledge during work experience. This raises questions for expertise
research: How do scientists themselves reason and how do they develop
these skills? The aim of this chapter is to summarise existing findings
about the relationship between expertise development and scientific
thinking.