The role of classification on testing conditional sentences in the context of an empirical task.

An analysis of a disjunctive concept based on 2 binary dimensions reveals that the relationships between the individual stimuli and classification are implicatory; these relationships may be expressed in conditional sentences of the form "if p then q." A 4-phase experiment with 40 students (average age 17 yrs 6 mo) was conducted to determine the effect on testing the truth value of conditional sentences of (a) prior experience in classifying the instances of the conditional, and (b) knowledge that such classifications would be of empirical value in a subsequent concept learning task. Phase I involved classifying individual stimuli for a subsequent concept learning problem; Phase II was the problem itself; Phase III was testing the truth value of 4 conditional sentences which, depending on whether they were true or false, described respectively the implicatory or tautologous relationships inherent in a concept learning task that followed (Phase IV). It is concluded that both prior experience with classifying the components of an implicatory rule and knowledge of the empirical relevance of such classifications to a subsequent task were necessary to the emergence of logical reasoning in the Phase III selection task. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)