"A fifth sort of argument concludes that defining art is philosophically unnecessary, on the grounds that the problem of defining art reduces to a pair of easier sorts of problems: the problem of giving an account of each individual artform, and the problem of defining what it is to be an artform. That is, given definitions of the individual artforms, and a definition of what it is to be an artform, and given, crucially, that every artwork belongs to some artform, a definition of art falls out: x is a work of art if and only if x is a work in activity P, and P is one of the artforms (Lopes, 2008). Every artwork belongs to an artform, on this view, because every artwork either belongs to an existing artwork or else pioneers a new artform. The key claim that every work of art belonging to no extant artform pioneers a new one may be defended on the grounds that any reason to say that a work belonging to no extant artform is an artwork is an artwork is a reason to say that it pioneers a new artform. In response, it is noted that an activity might be ruled out as an artform on the grounds that no artworks belong to it, and that the question of whether or not a thing belongs to an artform arises only because there is a prior reason for thinking that the thing is an artwork. (...)" - Amira

"The most prominent and influential institutionalism is that of George Dickie. Dickie's institutionalism has evolved over time. According to an early version, a work of art is an artifact upon which some person(s) acting on behalf of the artworld has conferred the status of candidate for appreciation (Dickie 1971)." :-) - Amira