Paul Graham is an essayist, programmer, and investor. In 1995 he developed with Robert Morris the first web-based application, Viaweb, which was acquired by Yahoo in 1998. In 2002 he described a simple statistical spam filter that inspired a new generation of filters. In 2005 he was one of the founders of Y Combinator. He and Robert Morris are currently working on a new Lisp dialect called Arc Paul is the author of On Lisp (Prentice Hall, 1993), ANSI Common Lisp (Prentice Hall, 1995), and Hackers & Painters (O'Reilly, 2004). He has an AB from Cornell and a PhD in Computer Science from Harvard, and studied painting at RISD and the Accademia di Belle Arti in Florence. Paulgraham.com got 8.9 million page views in 2009. Photo by Dave Thomas, released under the Attribution Creative Commons license. Click for full-size version.