The field of Artificial Intelligence has changed a great deal sincethe 80s, and arguably no one has played a larger role in thatchange than Judea Pearl. Judea Pearl's work made probabilitythe prevailing language of modern AI and, perhaps moresignificantly, it placed the elaboration of crisp and meaningfulmodels, and of effective computational mechanisms, at thecenter of AI research. This book is a collection of articles inhonor of Judea Pearl, written by close colleagues and formerstudents. Its three main parts, heuristics, probabilisticreasoning, and causality, correspond to the titles of the threeground-breaking books authored by Judea, and are followed bya section of short reminiscences.In this volume, leading authors look at the state of the art inthe fields of heuristic, probabilistic, and causal reasoning, inlight of Judea's seminal contributors. The authors list includeBlai Bonet, Eric Hansen, Robert Holte, Jonathan Schaeffer,Ariel Felner, Richard Korf, Austin Parker, Dana Nau, V. S.Subrahmanian, Hector Geffner, Ira Pohl, Adnan Darwiche,Thomas Dean, Rina Dechter, Bozhena Bidyuk, RobertMatescu, Emma Rollon, Michael I. Jordan, Michael Kearns,Daphne Koller, Brian Milch, Stuart Russell, Azaria Paz, DavidPoole, Ingrid Zukerman, Carlos Brito, Philip Dawid, Felix Elwert,Christopher Winship, Michael Gelfond, Nelson Rushton,Moises Goldszmidt, Sander Greenland, Joseph Y. Halpern,Christopher Hitchcock, David Heckerman, Ross Shachter,Vladimir Lifschitz, Thomas Richardson, James Robins, YoavShoham, Peter Spirtes, Clark Glymour, Richard Scheines,Robert Tillman, Wolfgang Spohn, Jian Tian, Ilya Shpitser, NilsNilsson, Edward T. Purcell, and David Spiegelhalter.