Correctness of Syllogistic Reasoning

The syllogistic inferences with cognitive statements are formal structures of thinking researched even from the Greek antiquity and make the subject of logics. The research of the modalities in which ordinary people reason in syllogistic structures is of a much more recent date, since the last century, and make the object of cognitive psychology. Our empirical study aims to investigate the correctness of thinking in various schemes of syllogistic reasoning. For this purpose we applied a set of four questionnaires, comprising 16 syllogisms each, of which 8 with affirmative conclusion and 8 with negative conclusion; 8 modes with universal conclusion, 8 modes with particular conclusion; each questionnaire includes four modes of each syllogistic figure. The first questionnaire contains complete syllogisms in formal expression, which the respondent must evaluate in terms of correctness. The second questionnaire contains the same premises as the first one, but the subjects are required to draw the proper conclusion themselves. Questionnaires 3 and 4 are analogous to the first two, except that this time syllogisms are formulated in natural language. Statistical processing involved comparing the number of correct answers in relation to the variables studied – syllogistic figure, valid/invalid syllogistic mode, affirmative/negative, universal/particular conclusion. The research was replied having been obtained similar results.