eng Science and Education Publishing American Journal of Applied Mathematics and Statistics 2328-7292 2013-12-27 2 1 1 6 10.12691/ajams-2-1-1 AJAMS2014211 article Michael Gr. Voskoglou 1 School of Technological Applications, Graduate Technological Educational Institute (T. E. I.) of Western Greece, Patras, Greece Human reasoning is characterized by a degree of fuzziness and uncertainty. In the present paper we develop a fuzzy model for a better description of the reasoning process and we use the fuzzy systems' total possibilistic uncertainty as well as the classical 's entropy (properly modified for use in fuzzy environments) in measuring the individuals' reasoning skills. Classroom experiments are also provided illustrating our results in practice. http://pubs.sciepub.com/ajams/2/1/1/ajams-2-1-1.pdf reasoningfuzzy setsmeasures of uncertainty