Martens R. Kepler's Philosophy and the New Astronomy

Princeton University Press, 2000, 216 p.Johannes Kepler contributed importantly to every field he addressed. He changed the face of astronomy by abandoning principles that had been in place for two millennia, made important discoveries in optics and mathematics, and was an uncommonly good philosopher. Generally, however, Kepler's philosophical ideas have been dismissed as irrelevant and even detrimental to his legacy of scientific accomplishment. Here, Rhonda Martens offers the first extended study of Kepler's philosophical views and shows how those views helped him construct and justify the new astronomy. Martens notes that since Kepler became a Copernican before any empirical evidence supported Copernicus over the entrenched Ptolemaic system, his initial reasons for preferring Copernicanism were not telescope observations but rather methodological and metaphysical commitments. Further, she shows that Kepler's metaphysics supported the strikingly modern view of astronomical method that led him to discover the three laws of planetary motion and to wed physics and astronomy-a key development in the scientific revolution. By tracing the evolution of Kepler's thought in his astronomical, metaphysical, and epistemological works, Martens explores the complex interplay between changes in his philosophical views and the status of his astronomical discoveries. She shows how Kepler's philosophy paved the way for the discovery of elliptical orbits and provided a defense of physical astronomy's methodological soundness. In doing so, Martens demonstrates how an empirical discipline was inspired and profoundly shaped by philosophical assumptions.Kepler’s Life and Times
Kepler’s Astronomical Inheritance
Kepler’s Philosophical Inheritance
The Mysterium cosmographicum and Kepler’s Early Approach to Natural Philosophy
The Content of the Mysterium cosmographicum
Kepler’s Cosmology
Kepler’s Approach to Natural Philosophy
Kepler’s Apologia: An Early Modern Treatise on Realism
Extra-Astronomical Considerations
The Nature of Astronomical Hypotheses
The Testing of Astronomical Hypotheses
Kepler’s ImprovedNotion of Testability
Concluding Remarks: The Archetypes
Kepler’s Archetypes and the Astronomia nova
The Status of Hypotheses in Physical Astronomy
The Replacement of the Mean by the True Sun
The Vicarious Hypothesis
The New Physics
Kepler’s Second Law
Oval Orbits
Physical andGeometrical Models of Libration
The Ellipse of Chapter 59
Archetypes in the Astronomia
The Aristotelian Kepler
The Aristotelian Challenge
Physical Astronomy as a MixedDiscipline