6/3/09 10 Software
Becoming familiar with common inference patterns and being able to use them via three new rules of inference and via rewrite rules. This helps with assessing ordinary everyday reasoning such as that found in the law, in newspapers, in advertisements, etc.
Bergmann[2008] The Logic Book Section 5.5
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.
6/1/09
6/2/09
6/2/09 10Software
Learning the Rules Or Elimination and the Introduction of the Biconditional.
Bergmann[2008] The Logic Book Section 5.1 and 5.4
Or Elimination, in the guise of Dilemma, also is a form of inference dating from antiquity.
3/16/06
So that we can show certain arguments to be valid.
The focus of the course lies with the validity and invalidity of arguments. Now, invalidity can be established by counter-example (by producing an interpretation under which all the premises are true and the conclusion false, at the same time). But validity is a different matter. And the usual approach is to have rules of inference and to do derivations.
6/2/09 10 Software
Learning reductio proof, both as plain Negation Introduction and via (double) Negation Elimination (to prove some formulas that do not have negation as their main connective).
Bergmann[2004] The Logic Book Section 5.1 and 5.4
Reductio ad Absurdum is the second of the classical forms of inference.
Tactics sometimes forces you to use these. And, on many other occasions you may simply wish to use them.
6/1/09