1.2.7 An Example

An example for a valid argument.

The argument with premises and and the conclusion is valid. That is,

As the reader may suspect, there is a connection between the validity of this argument and the fact that

Deduction Theorem.

The example suggests that with the help of the Boolean connectives and we can convert valid arguments into validities. This is exactly what's stated by the deduction theorem . The reader is asked to explore this possibility in Exercise 1.6 and Exercise 1.7.


Aljoscha Burchardt, Stephan Walter, Alexander Koller, Michael Kohlhase, Patrick Blackburn and Johan Bos
Version 1.2.5 (20030212)