ABSTRACT
The scientific achievements of Johannes Kepler have been described as a watershed moment in the history of humanity’s thinking about the universe. The greatest reasoner ever, for Charles Peirce, was the exemplar of abductive reasoning. This reasoning became possible for Kepler not by sleepwalking or curve-fitting but because of specific personal commitments and moral virtues. In this context, scientific reasoning is understood as a subclass of sense-making activities. Using Peirce’s framework of scientific inquiry and abductive inference, this chapter explores the psychological dimension of Kepler’s endeavor. His personal commitments to religious, metaphysical, and geometrical propositions are explicated, and their effects on his reasoning are shown. In the end, with Kepler as an example, some points are made about the nature of scientific attitude, the goal of scientific inquiry, and the causes of perversity in thought.
