The article includes presentation of fuzzy numbers application in projects prioritizing at

manufacturing and service providing enterprises. The following criteria have been applied

as a basis for projects prioritizing analysis in enterprise: NPV index, linked with the enterprise strategic aims, project execution cost, project time, project scope and risk. As the

criteria selected were of measurable and non-measurable character in projects prioritizing

evaluation, the fuzzy decision making system has been developed, in which a linguistic value

has been defined for each criterion of projects prioritizing. Knowledge base has been developed afterwards, presenting cause-effect dependencies in projects prioritizing. Knowledge

base consisted of conditional rules. Fuzzy system of decision making in project prioritizing

has been developed in MATLAB application.

The decision making fuzzy system established, constitutes an efficient tool for projects prioritizing, on the basis of criteria given and concluding system developed. The obtained analysis

results provide basis for the decision making parties to set the projects execution sequences.

On 24th March, 2017 Professor Józef Kozielecki passed away. He was a world renowned psychologist, a researcher into cognitive processes: thinking, problem solving, decision making. Professor Kozielecki was an author of the psychological theory of decision making, the theory of self-knowledge, and a founding father of the new direction in psychology, psychotransgressionism. An outstanding scholar, intellectual, theacher and a formative mentor for several generations of psychologists. He authored multiple important psychological monographs, for which he received national and international awards, for example, The Japanese Science Foundation award (1980) for his work on decision theory and The Jurzykowski Cultural Foundation award (1990) for his transgressive model of human beings. Professor Józef Kozielecki was a member of several prominent scientific societies such as the European Association of Experimental Social Psychology, the Society for Judgment and Decision making and the European Society for Cognitive Psychology. He was also an Ordinary Member of the Polish Academy of Sciences and in 2007 he received the honoris causa doctorate from the Catholic University of Lublin.