There are several antonyms for the phrase "art caused," which refers to something created or produced through artistic means. One antonym is "natural," which implies that something has not been manipulated or crafted by human hands. Another antonym is "accidental," which suggests that something has happened without any intentional creative effort. Additionally, "spontaneous" can be an antonym for "art caused," indicating that something has arisen freely and without conscious design. Finally, "inorganic" can serve as an antonym since it denotes things that are not imbued with any creative or artistic spirit.