Symmetry and transitivity assumptions about a nonspecified logical relation

Twenty-five subjects were presented with eight problems involving a non-specified relation, devoid of its concrete content. This relation was signified by the symbol (--), thus logically precluding any knowledge about the properties of the relation. The problems were so designed that the truth evaluation of their solution statements reflected assumptions about the symmetry and transitivity properties of the relation. Six subjects assumed that the relation was both symmetrical and transitive, and 12 subjects assumed that it was symmetrical only. When these same 18 subjects were presented with problems which lent themselves to only one of these assumptions, all assumed that the relation was symmetrical rather than transitive. The remaining seven subjects made neither of these two assumptions in any of the problems. Examples of logical relations, given as part of the problems, and varying in their properties of symmetry and transitivity, had no effect on the subjects' assumptions. It is proposed that symmetrical and transitive relations are conceptual good figures which predisposed subjects to perceive the nonspecified relation as symmetrical or as transitive. The stronger tendency towards symmetry assumptions than towards transitivity assumptions suggests that symmetrical relations are better figures than transitive relations.