Puu on taksonominen esitys kaikesta tiedosta. Sen inspiraationa on toiminut Francis Baconin teos Advancement of Knowledge. Puun kolme päähaaraa ovat "muisti" eli historia, "järki" eli filosofia ja "mielikuvitus" eli runous.
Robert Darnton, "Epistemological angst: From encyclopedism to advertising," in Tore Frängsmyr, ed., The structure of knowledge: classifications of science and learning since the Renaissance (Berkeley, CA: Office for the History of Science and Technology, University of California, Berkeley, 2001).