Earlier in the week I put up a website that allows one to click through the tree-like structure of Wittgenstein’s Tractatus Logico-Philosophicus in the Heap of Links (in the right sidebar). I believe the visualization is by Pierre Bellon, a web engineer who has “old-school philosophy” as a hobby. In response, David Stern (Iowa), sent in this helpful message: That’s a nice-looking website, but it runs into some problems when you look at the details.  In order to handle the relationship between proposition 3 and 3.001, its layout requires a node called “3.0” in between the two (which does not exist in the book’s numbering system).  And there is no “0” in the TLP numbering system, yet for some reason the site presents “0” as the base of the entire tree. Stern is currently teaching a graduate seminar on the topic of approaching the Tractatus as a logical tree (!). He continues: I’ve been giving this a lot of thought: the question of how to handle propositions such as 3.001 (and 3.0001) turns out to be a key issue for a systematic account of how the tree structure works. Luciano Bazzocchi has been publishing some very interesting work on this topic for some time–he makes a very strong case that Wittgenstein used the tree structure to compose the book out of his notebooks, and that it explains why Wittgenstein thought the numbering system, which no-one really understood until very recently, was so important. So, at Professor Stern’s suggestion, here is Bazzocchi’s depiction of the tree-like structure of the Tractatus. If you know of others, feel free to share them in the comments. UPDATE: A further update from Professor Stern: Actually, there are a surprising number of Tractatus tree/hypertext sites.  Two others, each slightly different, are: http://www.kfs.org/jonathan/witt/tlph.html http://tractatus-online.appspot.com/Tractatus_en.html There’s also Kevin Klement’s beautiful side-by-side-by-side edition, in various formats. (photo by JW)