著者

小林 剛

出版者

日本哲学会

雑誌

哲学 (ISSN:03873358)

巻号頁・発行日

vol.2004, no.55, pp.167-178,27, 2004-04-01 (Released:2009-07-23)

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In the ancient and medieval history of ideas, there seem to have been two main points of view concerning the character of astronomy. Some people believed that astronomy was a kind of geometry. Their position is, as it were, non-realistic. Others argued that astronomy had to be based on physical principles. Their position is, as it were, realistic. Thomas Aquinas seems to belong to the latter position. But his originality is to ground the hypothetical character of astronomy on the incorruptibility of celestial bodies. According to Thomas, astronomy is hypothetical because the human cognition of celestial bodies is uncertain. This uncertainty is caused by the incorruptibility of celestial bodies : celestial bodies are more perfect than sublunary bodies, which are the proper object of human cognition. In this way, Thomas grounds the limits of some human cognitions of nature on other human cognitions of nature, that is, on the human cognition of the metaphysical hierarchy in nature, for example, the distinctions between sublunary bodies and celestial bodies, celestial bodies and angels, and, angels and God. This metaphysical cognition is regarded as certain and grounds all other human cognitions of nature.