演者: Prof. Justin Erik Halldór Smith (Professeur des Universités Département d’Histoire et Philosophie des Sciences Université Paris Diderot – Paris VII Paris, France)
タイトル：Lunar Astronomy and Philosophy from Plutarch to Kepler
Why did so many philosophers in antiquity and the early modern period deploy thought experiments involving the moon?
What were their systematic and conceptual ends in this exercise?
In ancient astronomy,the moon served as an important boundary between two very different domains of nature, sometimes called the ‘superlunar’ and the ‘sublunar’ (or the ‘celestial’ and the ‘terrestrial’), which were subject to very different laws, not least the laws of generation, corruption, and motion.
The moon was also presumed, unlike the higher celestial bodies, to be in at least some traffic with the earth, with elements, and perhaps also beings, presumed to travel back and forth.
So to which side of the boundary did the moon itself belong?
In this talk, I would like to argue that it was precisely thisquestion that made the moon a fertile source of *Gedankenexperimente.*
From the utopian political subtexts of lunar science fiction of such authors as Cyrano de Bergerac, to the arguments for relativity in Johannes Kepler’s * Somnium*, the moon facilitated the
conceptualization of models of reality that could not be nearly so easily constructed on earth.
Thus people were effectively going into outer space, in the name of advancing theoretical understanding, long before such a feat was actually technically possible.
The way such thought experiments proceed,and what their real utility and pay-off are, may be important, I shall argue, for our understanding of the method of science more generally.