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Language, Proof and Logic


About the Authors

Jon Barwise and John Etchmendy are internationally known for their contributions to mathematical and philosophical logic, as well as for their pioneering work in the use of computers to enhance learning in logic, for which they were awarded the 1997 Educom Medal. The late Jon Barwise was College of Arts and Sciences Professor of Philosophy, Mathematics, and Computer Science at Indiana University. John Etchemendy was chairman of the Department of Philosophy at Stanford, and is currently provost of that university. Each has served as director of the Center for the Study of Language and Information at Stanford University.

Dave Barker-Plummer is an Senior Research Scientist at Stanford University's Center for the Study of Language and Information. He holds a Ph.D. from the Department of Artificial Intelligence at Edinburgh University. Since 1995 he has managed the Openproof project's work on educational software for teaching logic at the undergraduate level. He is the author of papers on automated reasoning, reasoning with diagrams, and architectures for heterogeneous reasoning. Dave has taught computer science and logic at Stanford, Swarthmore College and Duke University.

About the LPL Team

Language, Proof and Logic was conceived by Jon Barwise and John Etchemendy. Dave Barker-Plummer manages the project at Stanford University. Albert Liu contributed to many aspects of the software over a long period. Michael Murray's work is evident in all aspects of the desktop applications, and is primarily responsible for the web site as it currently appears. Emma Pease has served as the project's system administrator for the past two years. We have modernized the appearance of the LPL applications with this new release, and the graphical design work of Aaron Kalb is evident in every aspect of the software including the web site design, which was realized by Deonne Castaneda. Nik Swoboda of the Universidad Politécnica de Madrid created and maintains the Linux ports of the LPL software. Leslie Rogers served as the lead QA engineer for the new applications.

Gerard Allwein and Albert Liu were the lead programmers on the first versions of the program. Brad Dolin, Rachel Farber, Thomas S. Robertson, Alex E-Choon Lau and Rick Sanders contributed code. The LPL package would not be what it is without the dedication and hard work of all of these people, and many others, and we thank them all.


We have benefitted greatly from the feedback of the many instructors who have adopted the LPL package in their teaching. We would particularly like to thank Richard Zach, University of Calgary; S. Marc Cohen, University of Washington and Bram van Heuveln, Rensselaer Polytechnic Institute for much appreciated comments on the package. Bram suggested to us the addition of the "Add Support Steps" feature of the new Fitch program. Richard Johns of the University of British Columbia suggested the new "goggles" features which are also included in that program.

The Openproof project continues to benefit from generous funding from Stanford University and from its home in the intellectually stimulating environment of Stanford's Center for the Study of Language and Information (CSLI). As always, we are grateful to our publisher, Dikran Karagueuzian, and his team at CSLI Publications for their continued enthusiasm for LPL.