The gradual acceptance of the Copernican theory of the universeNote 11 — Chapter I · The Development of Astronomical Thought to 1400 A.D. A Preliminary Sketch of Early Theories as a Background.Reading editionCicero: Academica, Lib. II, c. 39 (322).◇Copy noteReturn to CHAPTER I. The Development of Astronomical Thought to 1400 A.D. A Preliminary Sketch of Early Theories as a Background.