The Physical Status of Astronomical Models Before the 1570s: The Curious Case of Lutheran Astronomer Georg Joachim Rheticus

The Doctrine of the Trinity: Intellectual Construct or Ontological Reality? Reflections from the Philosophy of Science

“…26 For Osiander and most sixteenth-century astronomers, Copernicus's hypothesis was an arbitrary geometrical instrument that helped coordinate the observations of astronomers. 27 It was simply an intellectual construct, a model of reality, a way of visualizing the solar system which 'preserved the phenomena'. Fictitious entities can thus have an explanatory capacity.…”

Tabula III: Kepler’s Mysterious Polyhedral Model

“…7 On 14 September 1595, Kepler wrote from Graz to his mentor Michael Mästlin (1550-1631), professor of mathematics at his alma mater, Universität Tübingen, convinced that his new geometrical solution explained the vast disparities between the planetary distances. 9 In the extended addendum to a second letter from 3 October 1595, Kepler gave his reasoning in a table that compared the observational data derived from Copernicus for the maximum and minimum distances of the planets' eccentricities in relation to the proportions derived from the Platonic solids. 10 Kepler's claim was extraordinary: the values of the planetary intervals generated from the regular solids approximated the data from Copernicus' De revolutionibus orbium coelestium (1543).…”