1. PHILOSOPHY 104 9.2 Notes

2. SOME DEFINITIONS:  Necessary: When A is a necessary condition for B, that means that condition A must be fulfilled before condition B can obtain, but that fulfilling condition A may not be by itself enough to fulfill condition B.  Sufficient: When A is sufficient for B, that means that all you need for B to obtain is for condition A to be fulfilled. However, condition B might still obtain without condition A being fulfilled.

3. THE CONDITIONAL  Conditional statements are called conditionals because they assert necessary and sufficient conditions.  In any given true conditional, the antecedent is a sufficient condition for the consequent, while the consequent is a necessary condition for the antecedent. S  N

4. TESTING NECESSARY AND SUFFICIENT CONDITIONS:  There are two tests for necessary and sufficient conditions: The conceptual test: formulate the conditions as a conditional statement in the appropriate way. True conditionals reveal what is a condition for what, while false conditionals reveal what isn’t a condition for what. The empirical test: The SCT and NCT of future slides.

5. THE NECESSARY CONDITION TEST (NCT)  Some feature F is a necessary condition for having feature G if and only if anything that lacks feature F also lacks feature G  Any feature F that is absent when G is present is eliminated as a possible necessary condition of G.

6. THE SUFFICIENT CONDITION TEST (SCT)  Some feature F is a sufficient condition for having feature G if and only if anything that has feature F also has feature G  So, any feature F that is present when G is absent is eliminated as a possible sufficient condition of G

7. THE JOINT TEST  A factor is necessary and sufficient in the case that it does not fail either NCT or SCT

8. RIGOROUS TESTING  If you’re looking for candidates for causal factors, make sure that you have enough examples of each feature’s presence and absence  This is to rule out coincidence