• The work of Daniel Sennert (1572-1637), professor of medicine at the Lutheran University of Wittenberg, encompasses the cluster of issues raised by the early seventeenth-century intersection of matter theories and the life sciences, where the origin of life emerged as one of the most important questions. There the belief in spontaneous generation was particularly pertinent. Sennert wrote a treatise precisely on this subject, entitled “De spontaneo viventium ortu,” published at the end of his masterpiece “Hypomnemata physica” (Frankfurt, 1636). There he developed a corpuscular interpretation of the origin of life to explain spontaneous generation, while biological generation provided the foundational model for his philosophical reflections in general. This article first analyzes Sennert’s discussions on the “normal” generation of living beings (plants, animals and human beings), the discussions which provide the basis of his doctrine on the origin of souls. Then his theory of spontaneous generation is examined on its own.

    1. Introduction
    2. The Origin of the Soul in Normal Generation
    2.1. The Giver of Forms and Astral Causality
    2.2. The Eduction of Forms
    2.3. Jacob Schegk and Plastic Force
    2.4. The Nature of the Seed and Its “Spiritus”
    3. Spontaneous Generation in Sennert
    3.1. The Soul, Seminal Principle and Corpuscles
    3.2. The Atoms of Living Beings and Their Souls
    4. Conclusions