U kontekstu obrata u vrednovanju naravi i nadnaravi u XIII. stoljeću misao Tome Akvinskoga o naravi kao otvorenoj nadnaravi prihvaćena je kao katoličko poimanje naravi. Cilj je ovoga rada ukazati na specifičnost Akvinčeva poimanja naravi, odnosno utvrditi značenje i važnost obilježja otvorenosti u sintagmi narav otvorena nadnaravi. U tu svrhu potrebno je razumjeti obilježja grčkog poimanja physis-a, a zatim i Aristotelovo poimanje naravi i težnje (grč. orexis). Ti uvidi pomažu razumjeti na koji se način Akvinčevo poimanje težnje (lat. appetitus ili inclinatio), a posljedično i naravi same, razlikovalo od Aristotelova. Usporedbom Aristotelovih i Akvinčevih poimanja naravi i težnje utvrđeno je da je Akvinac appetitus razumio kao začetak i sastavnicu dinamičnog odnosa naravi i nadnaravi koje tvore jedinstvenu cjelinu. U toj cjelini narav nije samo izvor promjene nego je raspoloživa primiti djelovanje vanjskog uzroka, a težnja se ne očituje samo kao neki pokret i usmjerenost nego i kao otvorenost (lat. dispositio) koja otkriva kakvo biće jest i predstavlja ontološki korijen srodnosti naravi u nadnaravi. In the context of the turn in the evaluation of nature and supernature in the 13th century, the thought of Thomas Aquinas on nature as open to supernature has been accepted as the Catholic understanding of nature. The aim of this article is to point out the specificity of Aquinas’s understanding of nature, i.e., to determine the meaning and importance of the characteristic of openness in the syntagma nature open to supernature. For that purpose, it is important to understand the characteristics of the Greek understanding of physics, as well as Aristoteles’s understanding of nature and striving (Greek orexis). These insights are helpful for discerning the manner in which Aquinas’s understanding of striving (Latin appetitus or inclinatio) and, consequently, nature itself, differed from Aristoteles’s understanding. By comparing Aristoteles’ and Aquinas’s understanding of nature and striving, the author concludes that Aquinas understood appetitus as the beginning and a constituent part of the dynamic relationship between nature and supernature that make one unique whole. On that whole, nature is not only the source of change but is also open to receiving the influence of an external cause, while striving is not only manifested as a movement and directedness but also as openness (Latin dispositio) that reveals the nature of being and represents the ontological root of cognition of nature in supernature.