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Tree Tutorial 1 Propositional Logic Truth Trees: Introduction

8/12/26

Graph theory and trees

'Trees' are a type of structure within the mathematical theory of graphs.

8/12/2026

Welcome!

Consistent

Invalid

7/3/06

1/24/06

eg Lander or Suber

The problem or issue here lies with the truth table for the conditional (or material implication)→

8/16/06 10Software

Skills to be acquired in this tutorial:

To learn how compound propositions are true or false depending on the truth or falsity of their component propositions.

There is the idea of setting up a code or convention or dictionary between atomic propositions and capital letters.

There are compound propositions, each of which has a main connective which connects its components.

There are five propositional logical connectives:

'∼' which translates back to 'it is not the case that...'

'&' which translates back to '... and ...'

'∨' which translates back to '... or ...'

'→' which translates back to 'if... then ...'

'≡' which translates back to '... if and only if ...'

8/29/06

Tutorial 2 Example: How Experts Symbolize

[This is a film-- press the 'play' symbol.]

8/29/06

7/30/08 11Software

Skills to be acquired in this tutorial:

To become familiar with the notions of argument, valid, invalid, premise, and conclusion. To learn how to symbolize atomic propositions.

Tutorial:

The main role of logic is to assess arguments-- to say whether an individual argument is valid or whether it is invalid. In logic, arguments are taken to consist of two components--premises, and a conclusion.

For example,

If it rains, I get wet.
It rains.

Therefore,

I get wet.