On 8/15/07, Andy Gimblett
I assumed he was just trying not to sing the "Spider Pig" song.
I've been banned from singing that around the house. And the cat version. But I was mainly thinking about how the physicist's definition of tensor needn't be accepted as an irreducible given, but is a consequence of the definition of tensor product through its universal property: http://planetmath.org/encyclopedia/TensorProduct.html Having said that, I still completely agree with Michael that tensors are a great analogy for monads because I found the concept of a universal property tricky in the same way that I subsequently found monads tricky. BTW I think the concept of a universal property is probably the single most useful idea from category theory that can be used in Haskell programming. I recommend it to everyone :-) -- Dan