Abstract: During the 1880s, Peirce began to develop a system of ‘scientific metaphysics’, an evolutionary cosmology that explains the evolution to a law-governed external world from a state of pure possibility. This appeals to his ‘tychism’, the view that there is absolute chance, and provides a defence of his realism. The chapter explores the emergence of this theme in his work, asking why it is required by his beliefs about logic and how it is related to other themes in his writing.

Keywords: chance, cosmology, evolution, laws, metaphysics, Peirce, realism,