Abstract
I argue that Copernicus accepted the reality of celestial spheres on the grounds that the equant problem is unintelligible except as a problem about real spheres. The same considerations point to a number of generally unnoticed liabilities of Copernican astronomy, especially gaps between the spheres, and the failure of some spheres to obey the principle that their natural motion is to rotate. These difficulties may be additional reasons for Copernicus's reluctance to publish, and also stand in the way of strict realism as applied to De Revolutionibus, although a realistic astronomy may be envisioned as a goal for Copernicus's research program.
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References
Aiton, E. J.: 1987, ‘Peurbach's Theorica novae planetarum’, Osiris 3, 5–44.
Ariew, R.: 1987, ‘The Phases of Venus Before 1610’, Studies in History and Philosophy of Science 18, 81–92.
Barker, P.: 1985, ‘Jean Pena and Stoic Physics in the Sixteenth Century’, in R. H. Epp (ed.), Recovering the Stoics, Southern Journal of Philosophy, 23 Supplement, 93–107.
Barker, P. and B. R. Goldstein: 1984, ‘Is Seventeenth Century Physics Indebted to the Stoics?’, Centaurus 27, 148–64.
Barker, P. and B. R. Goldstein: 1988, ‘The Role of Comets in the Copernican Revolution’, Studies in History and Philosophy of Science 19, 299–319.
Copernicus, N.: 1976, On The Revolutions of the Heavenly Spheres, A. M. Duncan (trans.), Barnes & Noble, New York.
Gabbey, A.: forthcoming, ‘Newton and the Libration of the Rotating Moon’ in P. Barker and R. Ariew (eds.), Revolution and Continuity, Catholic University of America Press, Washington.
Goldstein, B. R.: 1967, ‘The Arabic Version of Ptolemy's Planetary Hypotheses’, Transactions of the American Philosophical Society 57, part 4, 3–55.
Grant, E.: 1987, ‘Eccentrics and Epicycles in Medieval Cosmology’, in E. Grant and J. E. Murdoch (eds.), Mathematics and Its Applications in Science and Natural Philosophy in the Middle Ages, Cambridge University Press, Cambridge, England, pp. 189–214.
Jardine, N.: 1982, ‘The Significance of the Copernican Orbs’, Journal for the History of Astronomy 13, 168–94.
Neugebauer, O.: 1968, ‘On the Planetary Theory of Copernicus’, Vistas in Astronomy 10, 89–103.
Rosen, E.: 1975, ‘Copernicus' Spheres and Epicycles’, Archive Internationale d'Histoire des Sciences 25, 82–92.
Swerdlow, N.: 1972, ‘Aristotelian Planetary Theory in the Renaissance: Giovanni Battista Amico's Homocentric Spheres’, Journal for the History of Astronomy 3, 36–48.
Swerdlow, N.: 1973, ‘The Derivation and First Draft of Copernicus's Planetary Theory: A Translation of the Commentariolus with Commentary’, Proceedings of the American Philosophical Society 117, 423–512.
Swerdlow, N.: 1976, ‘Pseudodoxia Copernicana’, Archives Internationales d'Histoire des Sciences 26, 108–58.
Swerdlow, N. and O. Neugebauer: 1984, Mathematical Astronomy in Copernicus's De Revolutionibus, Springer, New York.
Van Helden, A.: 1985, Measuring the Universe, University of Chicago Press, Chicago.
Weisheiphl, J. A.: 1985, Nature and Motion in the Middle Ages, Catholic University Press of America, Washington.
Westman, R. S.: 1980, ‘The Astronomer's Role in the Sixteenth Century: A Preliminary Study’, History of Science 18, 105–147.
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Barker, P. Copernicus, the orbs, and the equant. Synthese 83, 317–323 (1990). https://doi.org/10.1007/BF00413764
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DOI: https://doi.org/10.1007/BF00413764