Further help with Reductio and Quiz 6
Quiz 6 Example of a difficult derivation
6/1/09
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.
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
6/1/09 10 Software
Learning conditional proof.
Bergmann[2008] The Logic Book Section 5.1 and 5.4
The five remaining core sentential rules of inference are slightly more difficult than the ones that we have met before. They are slightly more difficult in that they require you to make new assumptions, and the correct new assumptions at that. However they follow a similar pattern to each other so mastery of one should lead to mastery of the others.
12/22/05
This video is set in the context of the downloadable program, but it applies equally well in the setting of a proof applet.
5/29/09 10Software
a) Understanding the nature of derivation. b) Learning elementary Tactics.
Tactics will help you to do derivations.
Bergmann[2008] The Logic Book Section 5.1 and 5.4.
a)
A derivation or proof consists of a finite list of lines.