In the 21st Century, I opine that the definition of an Artist is anyone who produces an object which has an aesthetic primary function that has some form of value. The artist’s motivations, whether they are to produce something beautiful or simply to win admiration, are irrelevant. It is the nature of the art that is important.
By this definition, an interior decorator would not be an artist, because although she works in aesthetics, she does not actually produce objects, she merely arranges them. Whether someone who makes graffiti would be considered an artist depends on whether one consider graffiti to have value.
The major changes in society, in relation to their importance to art, since the renaissance, have been the declining rigidness of the class structure which allowed art to go from being an upper class enjoyment to one that was primarily judged by the middle class, resulting in a less rigid definition of art, and the increase in wealth and abundance of materials, which has allowed people to make art without having a patron. This has allowed an artist to be considered such without having any formal training. His work, however, in order to be considered art, and thereby for him to be considered an artist, must be primary aesthetic, and it must be aesthetically pleasing or valuable.
On two counts you might ponder:
Is arranging and rearranging the environment can be considered art? Remember the mirrors photographed in different locations in the MoMa exhibit? Or how about this artist who took the content of his parent shake and arranged it on the museum floor?
Artist sometimes will employ non-aesthetic quality to prove a point. Should they?