This article provides an historical overview of Ulpian’s praecepta iuris and focuses
on their roots in Greek philosophy and their role in Roman law. It alludes briefly to
the meaning of the praecepta in later legal literature such as the Glossa ordinaria and
the works of Kant. It reflects on the role of the praecepta in Roman-Dutch law, the
common law of South Africa. In Part 2 of this contribution, we explore the influence of
the praecepta iuris in present-day South African law, including African customary law.