playing your own fiddle

Three violin manufactures have all done business for years on the same block in the small town of Cremona, Italy. After years of a peaceful co-existence, the Amati shop decided to put a sign in the window saying: "We make the best violins in Italy." The Guarneri shop soon followed suit, and put a sign in their window proclaiming: "We make the best violins in the world." Finally, the Stradivarius family put a sign out at their shop saying: "We make the best violins on the block."