Description

This app provides the tools you will use most often in introductory symbolic logic courses.

* The logical notation can be chosen to match any textbook.
* Logical formulas are entered using a custom symbolic keyboard, which detects syntax errors.
* Lists of formulas can be saved and reloaded later.
* Truth tables can be generated for individual formulas, and sets of formulas can be tested for validity and consistency.
* Truth trees can be generated for selected sets of formulas.
* Derivations can be constructed in several different natural deduction systems, including "The Logic Book" and "Language, Proof, and Logic".
* Lines in the derivation editor are colour-coded to show assumptions and derived lines.
* The derivation editor tells you when the derivation is complete, and provides annotations for each line.

What's New in Version 2.3

Fixed a bug that prevented the derivation rules and annotation displays from working under OS 8.