I have also become intrigued and confused by this "category theory" and how it relates to Haskell. It has been stated many times that you don't need to understand category theory to utilize the Haskell language but all the concepts, patterns and every paper describing them seems to be written by someone who understands it. It really appears that to "innovate" in this community it helps to at least have a basic understanding of the theory. I have started working through this book "Conceptual Mathematics, A first introduction to categories" and so far it seems very understandable and interesting for mere mortals like myself. -- View this message in context: http://haskell.1045720.n5.nabble.com/category-design-approach-for-inconvenie... Sent from the Haskell - Haskell-Cafe mailing list archive at Nabble.com.