Art is "the class of objects subject to aesthetic criteria" seems to me a cop-out, like saying "philosophy is the totality of topics examined by philosophers." It doesn't say what art is.
Speaking of philosophers, don't go there to find a definition of art lest you find your brain twisted like a pretzel. [See Stanford University.] On the other hand, a less rigorous approach, which took up an entire book, defined art as "making special." Uhh, did I miss something?
Two definitions of art come close to the one I have settled on as my own. Tolstoy defined art as "a use of indirect means to communicate from one person to another." And John Ruskin defined art as "communication by artifice of an essential truth that could only be found in nature." [See Wikipedia.]
My definition: Art is a message to you from your own core which is mediated by someone else. This is true even if you yourself are the artist. And it follows that if a work of art doesn't speak to you, it is for you not art.
And there it is, to be analyzed, categorized, and criticized.
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