There’s not really that much to relate. For many years we have had a calendar of cat pictures, one of those where you tear off a sheet a day. Each picture is accompanied by a story about the cat pictured, or a piece of cat lore, or a grooming tip. Very occasionally it is simply a quote, and that’s how I picked this one up.
Hemingway’s fondness for cats is well-documented and he had something like 50, which makes our eight look unambitious. (NB for a change this is a cat puzzle not preceded by the death of one of them. They’ve all had a very good summer.) Many of Hemingway’s cats were polydactyls – with extra toes – and I did wonder about trying to work something of that into the puzzle. But it proved hard enough to get a reasonably long chain of cats. You tend to end up with Abyssinian, or Birman or similar and there aren’t many cats beginning with N. (Having seen a few Norwegian Forest cats at cat shows, I’m not convinced that they aren’t dogs in drag.)
Counting up the length of the chain gave the dimensions of the grid – and I was clearly going to be left with at least a single space in the perimeter (if not three, or five, or…); from that the idea of mirror symmetry evolved. Mirror symmetry can be a bit tricky when it comes to the unchecked letters, and I generally find that there are fewer of them. But in a puzzle where the whole perimeter is effectively unchecked that is no bad thing.