1 Objection 1: It would seem that the appetite is not a special power of the soul. For no power of the soul is to be assigned for those things which are common to animate and to inanimate things. But appetite is common to animate and inanimate things: since all desire good, as the Philosopher says Ethic. i, 1). Therefore the appetite is not a special power of the soul.
1 Ad primum sic proceditur. Videtur quod appetitus non sit aliqua specialis animae potentia. Ad ea enim quae sunt communia animatis et inanimatis, non est aliqua potentia animae assignanda. Sed appetere est commune animatis et inanimatis quia bonum est quod omnia appetunt, ut dicitur in I Ethic. Ergo appetitus non est specialis potentia animae.
2 Objection 2: Further, powers are differentiated by their objects. But what we desire is the same as what we know. Therefore the appetitive power is not distinct from the apprehensive power.
2 Praeterea, potentiae distinguuntur secundum obiecta. Sed idem est quod cognoscimus et appetimus. Ergo vim appetitivam non oportet esse aliam praeter vim apprehensivam.
3 Objection 3: Further, the common is not divided from the proper. But each power of the soul desires some particular desirable thing, namely its own suitable object. Therefore, with regard to this object which is the desirable in general, we should not assign some particular power distinct from the others, called the appetitive power.
3 Praeterea, commune non distinguitur contra proprium. Sed quaelibet potentia animae appetit quoddam particulare appetibile, scilicet obiectum sibi conveniens. Ergo respectu huius obiecti quod est appetibile in communi, non oportet accipi aliquam potentiam ab aliis distinctam, quae appetitiva dicatur.
4 On the contrary, The Philosopher distinguishes De Anima ii, 3) the appetitive from the other powers. Damascene also De Fide Orth. ii, 22) distinguishes the appetitive from the cognitive powers.
4 Sed contra est quod philosophus, in II de anima, distinguit appetitivum ab aliis potentiis. Damascenus etiam, in II libro distinguit vires appetitivas a cognitivis.
5 I answer that, It is necessary to assign an appetitive power to the soul. To make this evident, we must observe that some inclination follows every form: for example, fire, by its form, is inclined to rise, and to generate its like. Now, the form is found to have a more perfect existence in those things which participate knowledge than in those which lack knowledge. For in those which lack knowledge, the form is found to determine each thing only to its own being, that is, to its nature.
Therefore this natural form is followed by a natural inclination, which is called the natural appetite. But in those things which have knowledge, each one is determined to its own natural being by its natural form, in such a manner that it is nevertheless receptive of the species of other things: for example, sense receives the species of all things sensible, and the intellect, of all things intelligible, so that the soul of man is, in a way, all things by sense and intellect: and thereby, those things that have knowledge, in a way, approach to a likeness to God, in Whom all things pre-exist, as Dionysius says Div.
Nom. v). Therefore, as forms exist in those things that have knowledge in a higher manner and above the manner of natural forms; so must there be in them an inclination surpassing the natural inclination, which is called the natural appetite. And this superior inclination belongs to the appetitive power of the soul, through which the animal is able to desire what it apprehends, and not only that to which it is inclined by its natural form. And so it is necessary to assign an appetitive power to the soul.
5 Respondeo dicendum quod necesse est ponere quandam potentiam animae appetitivam. Ad cuius evidentiam, considerandum est quod quamlibet formam sequitur aliqua inclinatio, sicut ignis ex sua forma inclinatur in superiorem locum, et ad hoc quod generet sibi simile. Forma autem in his quae cognitionem participant, altiori modo invenitur quam in his quae cognitione carent. In his enim quae cognitione carent, invenitur tantummodo forma ad unum esse proprium determinans unumquodque, quod etiam naturale uniuscuiusque est. Hanc igitur formam naturalem sequitur naturalis inclinatio, quae appetitus naturalis vocatur. In habentibus autem cognitionem, sic determinatur unumquodque ad proprium esse naturale per formam naturalem, quod tamen est receptivum specierum aliarum rerum, sicut sensus recipit species omnium sensibilium, et intellectus omnium intelligibilium, ut sic anima hominis sit omnia quodammodo secundum sensum et intellectum, in quo quodammodo cognitionem habentia ad Dei similitudinem appropinquant, in quo omnia praeexistunt, sicut Dionysius dicit. Sicut igitur formae altiori modo existunt in habentibus cognitionem supra modum formarum naturalium, ita oportet quod in eis sit inclinatio supra modum inclinationis naturalis, quae dicitur appetitus naturalis. Et haec superior inclinatio pertinet ad vim animae appetitivam, per quam animal appetere potest ea quae apprehendit, non solum ea ad quae inclinatur ex forma naturali. Sic igitur necesse est ponere aliquam potentiam animae appetitivam.
6 Reply to Objection 1: Appetite is found in things which have knowledge, above the common manner in which it is found in all things, as we have said above. Therefore it is necessary to assign to the soul a particular power.
6 Ad primum ergo dicendum quod appetere invenitur in habentibus cognitionem, supra modum communem quo invenitur in omnibus, ut dictum est. Et ideo oportet ad hoc determinari aliquam potentiam animae.
7 Reply to Objection 2: What is apprehended and what is desired are the same in reality, but differ in aspect: for a thing is apprehended as something sensible or intelligible, whereas it is desired as suitable or good. Now, it is diversity of aspect in the objects, and not material diversity, which demands a diversity of powers.
7 Ad secundum dicendum quod id quod apprehenditur et appetitur, est idem subiecto, sed differt ratione, apprehenditur enim ut est ens sensibile vel intelligibile; appetitur vero ut est conveniens aut bonum. Diversitas autem rationum in obiectis requiritur ad diversitatem potentiarum; non autem materialis diversitas.
8 Reply to Objection 3: Each power of the soul is a form or nature, and has a natural inclination to something. Wherefore each power desires by the natural appetite that object which is suitable to itself. Above which natural appetite is the animal appetite, which follows the apprehension, and by which something is desired not as suitable to this or that power, such as sight for seeing, or sound for hearing; but simply as suitable to the animal.
8 Ad tertium dicendum quod unaquaeque potentia animae est quaedam forma seu natura, et habet naturalem inclinationem in aliquid. Unde unaquaeque appetit obiectum sibi conveniens naturali appetitu. Supra quem est appetitus animalis consequens apprehensionem, quo appetitur aliquid non ea ratione qua est conveniens ad actum huius vel illius potentiae, utpote visio ad videndum et auditio ad audiendum; sed quia est conveniens simpliciter animali.