CELESTIAL MOVERS IN MEDIEVAL PHYSICS 175 



ductive of higher forms. One can say that these higher forms 

 produced preexist in the elements virtually insofar as these 

 elements are instruments of celestial movers. Of course, the 

 celestial mover is itself a voluntary, intellectual instrument of 

 the absolutely first intelligence, which is God. Similarly the 

 male sperm virtually and actively contains the living and sen- 

 tient souls of the embryo, but only as the instrument of celes- 

 tial forces and intelligences. In other words, the natural heat, 

 density, mobility and structure of the male sperm are used 

 instrument ally by celestial agents to produce an effect higher 

 than their own active powers. ^^ It was in this way that St. 

 Albert understood and explained the famous Aristotelian 

 phrase. Homo ex materia generat hominem et sol. (Phys. II, 

 2, 194bl3) .''^ The only qualification which Albert, the phi- 

 losopher and theologian, makes to this phrase is the direct 

 creation of the human soul.'^ 



Finally, for Albert, the separated movers of celestial bodies 

 are the active intelligences {intellectus agens) . Each intelli- 

 gence is like a practical intellect of an artist who conceives the 

 image to be produced and implants this in his instruments as 

 he uses them. The instruments of the active intelligence are 

 three-fold, namely the conjoined spiritual mover, the celestial 

 body itself, and the inherent powers of terrestrial nature. Con- 

 sequently the ultimate mover of each celestial body is, in fact, 

 the separated active intelligence proportioned to the spheres. 

 Since, however, all celestial spheres depend upon the diurnal 

 motion of the first heaven, the absolutely first mover of all the 

 celestial bodies is the separated, active intelligence command- 

 ing the primum caelum. This absolutely first mover is the 

 primum principium universi esse, the cause not only of all 



75 

 7« " 



' St. Albert, Problemata determinata, q. 34; De animalibiis XVI, tr. I, cc. 11-13. 

 ' Quod enim impressiones separatorum a materia generabilium sint in materia 

 patet per hoc quod ex materia hominis homo generat hominem, et sol et motor 

 solis; et ideo oportet considerare separata in quantum impressiones earum per 

 motum caelestium sunt in generabilibus et corruptibilibus." St. Albert, Lib. 11 

 Phys., tr. I, c. 11, ed. cit., pp. 113-4. See Averroes, ibid., comm. 26. 



''"' Problemata determinata, q. 33; De nat. et orig. animae, tr. I, c. 5; De animxi- 

 libus, lib. XVI, tr. I, cc. 11-12; Summa de creaturis, P. II, q. 5, a. 4. 



