抄録
In this paper, the author attempts to clarify to what extent the coordinate relations theoretically hold among the Copernican, the Tychonian, and the Ptolemaic world systems as they are compared by means of simplified models consisting of combined uniform circular motions. The results are:
(1) Concerning the apparent positions and movements of the planets against the celestial sphere, there can be exact coordinate relationships among the three systems.
(2) Concerning the distance from the observer, the visual size and brightness, and the phase of the planets, any of these systems can give satisfactory accounts of the phenomena observed with the naked eye, although exact coordinate relationships in these respects do not quite hold among the three systems.
From the above, the present author concludes that the naked eye observations before the telescopic ones could not have established the superiority of the Copernican system over the others. The author also presents a new interpretation concerning A. OsianderJs description of the changes in brightness of Venus given in his Foreword to De Revolutionibus, and points out some of the related errors made in the recent historical investigations of the world systems.
