Doug Lenat

Title: Lisp and Common Sense: Are They Allies or Adversaries?

Abstract: Most of our development of the Cyc common sense knowledge AI system has taken place in Lisp, notably the inference engine, interfaces, and underlying knowledge representation data structures and access functions.   Over the course of this large effort (650 person-years spent over the last 18 years), we've learned a lot about AI, common sense, and the use of Lisp in an effort of this magnitude.  I'll share some of those lessons learned, along with some interesting anecdotal experiences, meta-experiences (such as what people mean when they list Lisp on their resume'), and hard decisions made (such as when we finally abandoned symbolics machines as our development machines, and why).