2250 Lecture Notes - Syllogism, Modus Tollens, Logical Biconditional

• School: Buffalo State College
• Department: Philosophy
• Course: 2250
• Professor: James Hildebrand

Document Summary

Strategies for constructing derivations in sd (apply the following strategies in the order they are listed: ve strategy: If any of the sentences you have is a disjunction split your derivation into two successive sub-derivations. Head the first part off with the assumption of the first disjunct and attempt to derive your goal sentence under this assumption. Head the second part off with the assumption of the second disjunct and do the same. Apply ve to get the goal sentence outside of the two sub-derivations: i/ i strategy: If your goal sentence is a conditional, assume the antecedent and try to derive its consequent under the scope of this assumption. If your goal sentence is biconditional, split your derivation into two successive sub-derivations. In the first, assume one component of the biconditional and attempt to derive the second component under this assumption.