Many have argued that it is a mistake to even try to define art or beauty, that they have no essence, and so can have no definition. Often, it is said that art is a cluster of related concepts rather than a single concept. Examples of this approach include Morris Weitz and Berys Gaut.
Andy Warhol exhibited wooden sculptures of Brillo Boxes as art.
Another approach is to say that “art” is basically a sociological category, that whatever art schools and museums, and artists get away with is considered art regardless of formal definitions.
This institutional theory of art has been championed by philosopher George Dickie. Most people did not consider a store-bought urinal or a sculptural depiction of a Brillo Box to be art until Marcel Duchamp and Andy Warhol (respectively) placed them in the context of art (i.e., the art gallery), which then provided the association of these objects with the values that define art.
Proceduralists often suggest that it is the process by which a work of art is created or viewed that makes it, art, not any inherent feature of an object, or how well received it is by the institutions of the art world after its introduction to society at large.
For John Dewey, for instance, if the writer intended a piece to be a poem, it is one whether other poets acknowledge it or not.
Whereas if exactly the same set of words was written by a journalist, intending them as shorthand notes to help him write a longer article later, these would not be a poem.
Dalmau is a firm believer that as an art form, found objects tend to include the artist's output—at the very least an idea about it, the artist's designation of the object as art—which is nearly always reinforced with a title.
There is usually some degree of modification of the found object, although not always to the extent that it cannot be recognized, as is the case with ready-mades. Recent critical theory, however, would argue that the mere designation and relocation of any object, ready-mades included, constitutes a modification of the object because it changes our perception of its utility.(Source Wikipedia)