“The narrative that tells of the first man and woman encountering the tree of knowledge focuses on its tempting fruit. But after we took the bite, we apparently looked up and got the idea that knowledge is shaped like the tree’s branching structure: Big concepts contain smaller ones that contain smaller ones yet. Over the millennia, we have fashioned the structures of knowledge in just such tree-like ways, from the departmental organization of universities (liberal arts contains history and history contains ancient Chinese history) to the hierarchy of species. The idea that knowledge is shaped like a tree is perhaps our oldest knowledge about knowledge.” (David Weinberger – JOHO)