- Contents
- 1 Before starting...

- 2 Basic concepts

- 3 Natural deduction

- 4 The derivation rules
- 4.1 Iteration
- 4.2 Conjunction introduction
- 4.3 Conjunction elimination
- 4.4 Implication introduction
- 4.5 Implication elimination
- 4.6 Disjunction introduction
- 4.7 Disjunction elimination
- 4.8 Negation introduction
- 4.9 Negation elimination
- 4.10 No more rules

- 5 Explained exercises
- 5.1 A very simple one.
- 5.2 A bit more complicated.
- 5.3 Starting to make suppositions.
- 5.4 Using iteration.
- 5.5 Reduction to the absurd.
- 5.6 With subdemonstrations.
- 5.7 One with proof by cases.
- 5.8 One to think.
- 5.9 Left side empty.
- 5.10 Suppose the contrary.
- 5.11 This one seems easy.
- 5.12 An interesting one.
- 5.13 I had this one in an exam.
- 5.14 A ``short'' one.

- 6 Wrong things
- 6.1 Introduction and elimination of ``what it would be nice to have''
- 6.2 Iterate something from a non attainable subdemonstration
- 6.3 Misplace parenthesis
- 6.4 Finish inside a subdemonstration
- 6.5 Skip steps

- 7 Making it harder

- 8 Extra
- 8.1 Why is it called natural deduction?
- 8.2 Is the solution unique?
- 8.3 Other ways to prove validity
- 8.4 How to prove invalidity
- 8.5 Create your own exercises
- 8.6 Programs which do natural deduction

- 9 Examples, lots of examples
- 9.1
- 9.2
- 9.3
- 9.4
- 9.5
- 9.6
- 9.7
- 9.8
- 9.9
- 9.10
- 9.11
- 9.12
- 9.13
- 9.14
- 9.15
- 9.16
- 9.17
- 9.18
- 9.19
- 9.20
- 9.21
- 9.22
- 9.23
- 9.24
- 9.25
- 9.26

- About this document ...

Daniel Clemente Laboreo 2005-05-17