A very complex question. Art exists on more than one level. It is also very subjective. Painting is an easy form to use for example.
For some folks, Elvis on black velvet is as good as art gets. Despite his unbelievable success, many people think that most of Picasso's work is ugly. I have no idea where my love of impressionism came from, but can say honestly that almost everything I've seen by Monet and Pissaro just knocks me out.
In knives, I tend to look most at design in determining art, I guess. I like simple, clean lines, and I don't mind knives that push the envelope a bit in terms of usefulness. But, design that doesn't just leap out at you, that is felt in ergonomics, in comfortable handles for long hours of work, little things that make a knife so much more effective to use than the great mass of them, that is art too.
One of my personal favorites amongst knifemakers, solely because of design, since I've never touched one of his knives, is Thomas Haslinger. In both his "regular" knives and his "art knives" I see beauty and economy of line that just really grabs me. In case you wish to check him out, here is his URL:
http://members.home.net/thknives/
Ultimately, it is all personal. I'm sure thousands of Buck 110 owners will go to their graves convinced that is a beautiful knife. A lot of Spyderco fans are wild about the Gunting's design, while others favor the Civilian. Many would see either design as just plain ugly.
I think that maybe there is at least one aspect of knives that transcends the personal/subjective. That is purpose. If a knife is built for a specific purpose and hits the mark, is able to fulfill entirely the intended purpose, then that is probably art, regardless of appearance.
Just my $.02 worth.
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Asi es la vida
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