What is Deductions?
Logic software that accelerates learning by giving immediate feedback, providing interactive help, and making natural deduction easy.
See Errors Immediately
Errors are flagged as soon as they are made.
Help at Your Fingertips
Video tutorials and hints are one click away.
Promote Good Habits
Assumptions must have explicit exit strategies.
Quick and Easy
Automatically renumbers lines and justifications.
Use with Your Textbook
Many texts, symbols and rulesets supported.
Fits Any Budget
Elegant software for the cost of a pizza.
Easy to use and intuitive.
– Patrick Holt, Research Professor
The Wandering Blog
Deductions 1.2(15 January 2010 | 3:54 pm)
Deductions 1.2 is out. This version sees the addition of 45 new rules and aliases, to bring the total number of rules supported to 85 (!), with each rule being able to be turned on and off individually. Also, we have expanded the number of textbooks supported “out of the box” to ten:
(1) The Logic Book (Bergmann/Moor/Nelson, 2008)
(2) A Serious Introduction to Mathematical Logic (Roy, 2009) (Free online)
(3) A Modern Formal Logic Primer (Teller, 1989) (Free online)
(4) Logics by (Nolt, 1996)
(5) Symbolic Logic by (Jacquette, 2000)
(6) A Concise Introduction to Logic (Hurley, 2008)
(7) Introduction to Logic (Copi/Cohin, 2008)
(8) Logic and Philosophy (Hausman/Tidman/Kahane, 2009)
(9) The Power of Logic (Howard-Snyder/Snyder/Wasserman, 2008)
(10) Modern Logic (Forbes, 1994)
Fuzzy string-matching has also been implemented when citing rules, to make it easier to enter justifications. Documentation has been updated across-the-board to reflect these major changes.
This release is accompanied by an entirely reworked website with more obvious navigation buttons and a simpler presentation.