propositional

Or Introduction

Help for Tutorial 5

9/4/06

Tutorial 5 Example: Doing a derivation

This movie shows the downloadable application being used, but the manipulations are so similar to those of the web page applet that it really covers both.

5/18/09 10Software

Skills to be acquired in this tutorial:

Proving an argument to be valid by displaying a derivation. Simple sentential derivations using some of the Rules of Inference.

Reading

Bergmann[2004] The Logic Book Section 5.1.

The Tutorial:

If you suspect that an symbolized argument might be valid, you should attempt to give a derivation of it.

A derivation is a proof of validity.

5/18/09

Review of new material

There are the truth-tables for the connectives...

Negation

F ∼F True False False True

Conjunction

2013

You need to know some propositional logic to be able to understand the tutorials to come. In particular, you need to know about the symbols used in propositional logic, truth tables, satisfiability, consistency, and semantic invalidity (by counter example). You do not need to know propositional rules of inference and derivations.

Howson [1997] will give you enough background.

Alternatively you could look at the first five propositional tutorials in Easy Deriver

12/19/20

Welcome!

The tutorials presented here look at some topics in logic to the level of intermediate to advanced Predicate Calculus. They build on the Tutorials of Easy Deriver which provided the introductory material to Propositional and Predicate Calculus.

The program, widgets, or Notes, should be accompanied by a suitable textbook, such as:

Welcome!

These web pages provide an introduction to logic to the level of Propositional and Predicate Calculus.

The focus of the program is on arguments and the question of whether they are valid. Arguments have the form <list of premises> ∴<conclusion>. An argument is valid if and only if it is not possible for all its premises to be true and its conclusion false at one and the same time; an argument which is not valid is invalid.

10/8/26

Welcome!

These web pages provide an introduction to logic to the level of Propositional and Predicate Calculus.

The focus of the program is on arguments and the question of whether they are valid. Arguments have the form <list of premises> ∴<conclusion>. An argument is valid if and only if it is not possible for all its premises to be true and its conclusion false at one and the same time; an argument which is not valid is invalid.