# semantics

## Tutorial 23: The semantics of relations

###### 12/24/13

### The Tutorial

The semantics of relations proceeds in much the way one would expect-- the new item that has to be taken account of is the order of the terms (because, for example, Tab is not at all the same thing as Tba -- Arthur being taller than Beryl is not the same as Beryl being taller than Arthur).

Let us start with an Interpretation

Interpretation 1

Universe= {a,b}

F={a}

## Help with the semantics of free variables

12/25/06

### Introduction to Free Variables

This video illustrates use of the downloadable application (and the symbol ∧ for 'and' and (∀x) for the universal quantifier, some systems use (x) for this). But, what the film depicts and explains is equally good if you happen to be using the web pages applets (or different symbols for 'and' and the universal quantifier).

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## Tutorial 17: The semantics of quantifiers

2013

### The Tutorial

We will certainly wish to discuss the truth and falsity of formulas with quantifiers in them.

Let us start with an Interpretation

Interpretation 1

Universe= {a,b}

F={a}

## Tutorial 14: Some Terminology for the Semantics of Predicate Logic

###### 8/4/13

### The Tutorial

A few concepts are needed give a simple portrayal of the truth and falsity of predicate logic formulas.

There is the notion of an Interpretation which consists of a Universe together with an account of how the various symbols in the predicate logic formulas apply in this Universe.

There should be a Universe, which is the collection of the objects that the formulas is about. We write, for example,

Universe = {a,b,c}

## Help with Introductory Semantics

## Introduction to Semantics

12/25/06

### Introduction to Semantics

This video illustrates use of the downloadable application (and the symbol ∧ for 'and'). But, what it depicts and explains is equally good if you happen to be using the web pages applets (or a different symbol for 'and' eg '.').

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## Predicate Logic: 15 Tutorials

There are many valid arguments which cannot be shown to be valid using sentential logic alone. For example,

Beryl is a philosopher.

All philosophers are wise.

Therefore

Beryl is wise.

## Help with First Three Propositional Games, if you need it

5/15/12

### Propositional Main Connective

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### Propositional Truth Table Line

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## Help with Tutorial 3, if you need it

8/29/06

### Tutorial 3 The Main Connective Applet

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## Tutorial 3: Sentences and Truth

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6/8/07 10Software

### Skills to be acquired in this tutorial:

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