CELESTIAL MOVERS IN MEDIEVAL PHYSICS 151 



Robert Kilwardby, later archbishop of Canterbury, was dis- 

 covered and published by Fr. M.-D. Chenu, O. P., about thirty 

 years ago.^ Now with the discovery and publication of the 

 reply of the third consultor, the great St. Albert himself,* we 

 are in a position to compare the views of the three Dominican 

 Masters point by point. 



Among the relatively few interesting questions in the list of 

 forty-three, the first five stand out as particularly important for 

 the historian and philosopher of science. They have to do with 

 the cause or causes of celestial motion. In the order of appear- 

 ance they are as follows: 



1) Does God move any physical body immediately.? 



2) Are all things which are moved naturally, moved under 

 the angels' ministry moving the celestial bodies.? 



3) Are angels the movers of celestial bodies.? 



4) Is it infallibly demonstrated according to anyone that 

 angels are the movers of celestial bodies? 



5) Assuming that God is not the immediate mover of those 

 bodies, is it infallibly demonstrated that angels are the 



movers of celestial bodies.? 



To the casual reader these questions, too, might appear to be 

 useless in this age of scientific progress. Angels, it is frequently 

 thought, have no place in a discussion of scientific questions. 

 Some Catholic scientists, and even some Thomistic philosophers 

 feel considerable embarassment at the mention of angels; they 

 would rather not mention them at all, or at least not mention 

 them as having anything to do with the real world in which 

 we live. In medieval literature the problem of celestial movers 

 was not created by theologians, nor did it take its origin in 

 any point of Catholic faith, although St. Thomas was keenly 



' M.-D. Chenu, O. P., " Les Reponses de s. Thomas et de Kilwardby a la con- 

 sultation de Jean de Verceil (1271)," in Melanges Mandonnet (Bibl. Thomiste 

 XIII: Paris 1930), vol. I, pp. 191-222. 



* James A. Weisheipl, O. P., " The Problemata Determinata XLIII Ascribed to 

 Albertus Magnus (1271)," in Mediaeval Studies, XXII (1960), 303-354. 



