Intellectual humility of Domingo de Soto, O.P.

[Geremia]

Part 3 ch. 18 of

• Duhem, Pierre Maurice Marie. Études sur Léonard de Vinci, ceux qu'il a lus et ceux qui l'ont lu. Vol. 3. 3 vols. Paris: A. Hermann, 1906, pp. 286-290,

entitled "Soto tries to make the views of Aristotle and St. Thomas agree with the hypothesis of impetus," quotes:

• De potentia q. 3 a. 11 ("Is the Sensible and Vegetal Soul Created or Is it Transmitted Through the Semen?") ad 5 (ca. 1265-6):
  

  Ad quintum dicendum, quod instrumentum intelligitur moveri a principali agente, quamdiu retinet virtutem a principali agente impressam; unde sagitta tamdiu movetur a proiciente, quamdiu manet vis impulsus proicientis. Sicut etiam generatum tamdiu movetur a generante in gravibus et levibus quamdiu retinet formam sibi traditam a generante; unde et semen... Oportet autem movens et motum esse simul quantum ad motus principium, non tamen quantum ad totum motum, ut apparet in proiectis.

  An instrument is understood to be moved by the principal agent so long as it retains the power communicated to it by the principal agent; thus the arrow is moved by the archer as long as it retains the force wherewith it was shot by him. Thus in heavy and light things that which is generated is moved by the generator as long as it retains the form transmitted thereby: so also with the seed... And the mover and the thing moved must be together at the commencement of but not throughout the whole movement, as is evident in the case of projectiles.

• De anima q. 1 a. 11 ("Whether the rational, sentient, and vegetal souls in man are substantially one and the same") ad 2 (ca. 1265-6)
  

  virtus quae est in semine a patre, est virtus permanens ab intrinseco, non influens ab extrinseco, sicut virtus moventis quae est in proiectis ... Tamen quantum ad aliquid est simile: sicut enim virtus proiicientis, quae est finita, movet motu locali usque ad determinatam distantiam loci, ita virtus generantis movet motu generationis usque ad determinatam formam.

  The power existing in the semen which is derived from the father is a permanent intrinsic power, not one coming from an extrinsic principle, just as the power of the mover which exists in the thing thrown is intrinsic. ... Nevertheless there is some similarity here, because, just as the thrower's power, which is finite, moves an object to a definite place some distance away by local motion, so does the power of one generating move a thing to a determinate form by the movement of generation.

• De cælo lib. 3 l. 7 ("Every body moving naturally in a straight line has either gravity or lightness, Natural and violent motions") n. 6 (cf. 1272-3):
  

  Non est autem intelligendum quod virtus violenti motoris imprimat lapidi qui per violentiam movetur, aliquam virtutem per quam moveatur, sicut virtus generantis imprimit genito formam, quam consequitur motus naturalis: nam sic motus violentus esset a principio intrinseco, quod est contra rationem motus violenti. Sequeretur etiam quod lapis, ex hoc ipso quod movetur localiter per violentiam, alteraretur: quod est contra sensum. Imprimit ergo motor violentus lapidi solum motum: quod quidem fit dum tangit ipsum. Sed quia aer est susceptibilior talis impressionis, tum quia est subtilior, tum quia est quodammodo levis, velocius movetur per impressionem violenti motoris, quam lapis: et sic, desistente violento motore, aer ab eo motus ulterius propellit lapidem, et etiam aerem coniunctum; qui etiam movet lapidem ulterius, et hoc fit quousque durat impressio primi motoris violenti, ut dicitur in VIII Physic. Et inde est quod, quamvis motor violentus non sequatur ipsum mobile quod per violentiam fertur, puta lapidem, ut praesentialiter ipsum moveat, tamen movet per impressionem aeris: si enim non esset tale corpus quale est aer, non esset motus violentus.

  This does not mean that the force of the violent mover impresses upon the stone which is moved by violence some force by which it might be moved, in the way that the power of the generator impresses on the thing generated a form upon which natural motion follows — for then the violent motion would proceed from an intrinsic principle, and that is contrary to the notion of a violent motion. It would also follow that a stone, by the very fact that it is in local motion through violence, would be altered — and this is contrary to what we sense. Therefore, the violent mover impresses motion alone upon the stone, and this it does while it touches it. But because air is more susceptible to such an impression (both because it is more subtle and because it is in a sense light), it is moved more swiftly through the impression of the violent mover than the stone. Consequently, when the violent mover desists, the air moved by it continues to propel the stone and also the adjoining air, which likewise moves the stone farther, and this continues so long as the impression of the first violent mover endures, as is said in Physics VIII. Hence it is that the violent mover, even though it does not follow the mobile that is being carried along through violence, e.g., a stone, so as to move it by being present to it, yet it moves it through the impression of the air —if there were no body such as is the air, there would not be violent motion.

Duhem's chapter manifests the intellectual humility of Fr. Domingo de Soto, O.P., because, although quotes #1 and #2 above make it seem as though St. Thomas would've endorsed Buridan's impetus theory, in the end Fr. De Soto realized this is not true due to quote #3 above (De Cælo is St. Thomas's last work, so quote #3 could be seen as his final word on the subject). Fr. De Soto follows reason instead of straining to reconcile St. Thomas and Aristotle with the impetus theory.

[Geremia]

"You have to be willing to pursue the truth wherever it leads, regardless of the personal cost to you, because if you don't have the truth, then it's already costed you."

—Fr. Chad Ripperger on intellectual humility (vs. what he calls intellectual effeminacy)