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Logical Reasoning with Diagrams and Sentences

Dave Barker-Plummer, Jon Barwise and John Etchemendy

in collaboration with

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 a 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.


The publication of Logical Reasoning with Diagrams and Sentences is the culmination of a process involving a large cast of characters. The Hyperproof program has been completely rewritten, although it shares some code with our program Fitch and some with Tarski's World. Michael Murray has been largely responsible for knitting the many pieces together and producing the implementation of Hyperproof that you have on your computer. Albert Liu, Andrei Aron and Murad Akter contributed significantly to the development effort. Olalere Williams developed the exercise files and a set of solutions to them, encountering and reporting many bugs on the way. Adeline Wong, Leslie Rogers, Su Su and Quinn Barker-Plummer all assisted with QA on the application and text book. Aaron Kalb and his formidable graphical design skills are responsible for the updated design of the 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 enthusiasm for LRDS.

Logical Reasoning with Diagrams and Sentences was first published under the name Hyperproof for the Macintosh (8.5) platform only, and without the Grade Grinder grading service. Details of the team that produced the original version can be found in the text book.