The word heuristic came from the greek and means “I found it!”; it has the same semantical roof than the expression eureka from Newton. For understanding the function of heuristic in art, it is necessary to realize that every creative need some principles, ideas and convictions more and less systematic as a starting point of her/his work. But this principles, ideas and convictions are not true or false. We say they are appropriate or not for the purpose that the artist (...) intends or not. In this sense, assumptions, theories and fictions could belong to the heuristic of an artist whether they allow the artist to reach the artistic goal she/he is looking for. Between theory and practice, heuristic is the pretext the artist found to explain plausibly and credible the production of art. (shrink)