5.6ex VIII
Logical Falsehood and Inconsistency

Each of the following problems requires that

• you give a derivation in SD to show either
  • that a single sentence is logically false or
  • that a set is logically inconsistent.
• You are to take the individual sentence as premise (for showing logical falsehood) or the set as the set of premises (for showing logical inconsistency).
• Then derive any sentence and its negation.