Effects of Structure and Semantics on the Solution of Pure Hypothetical Syllogisms

A report of an investigation examining the relative effects of a structural factor (i.e., premise order) and a semantic factor (i.e., negation in the minor premise) on adults' abilities to reason with pure hypothetical syllogisms. The Ss in this investigation were 36 undergraduate (juniors and seniors) and 36 graduate (doctoral) students. The results indicated that premise order had a significant effect on the deductive reasoning abilities of undergraduates. However, neither negation in the minor premise nor the interaction of this factor and premise order had a significant effect on the deductive reasoning abilities of Ss at either academic level. The results of the present study, and those of previous studies, were compared in terms of: (1) types of syllogism; (2) types of syllogistic content; and (3) principles of inference that were employed.