We live, unfortunately, in turbulent and difficult times plagued by
various political, economic, and social problems, as well as by natural
disasters worldwide. Systems become more and more complicated, and this
concerns all levels, exemplified first by global political alliances,
groups of countries, regions, etc., and secondly, by multinational
(global) corporations and companies of all sizes. These same concerns
affect all social groups. This all makes decision processes very
complicated. In virtually all decision processes in these complicated
systems, there are various actors (decision makers) who represent
individual subjects (persons, countries, companies, etc.) and their
respective interest groups. To reach a meaningful (good) decision,
opinions of all such actors must be taken into account or a given
decision may be rejected and not implemented. Ideally, a decision would
be made after a consensus between the parties involved had been
attained. So, consensus is a very desirable situation. In most
real-world cases there is considerable uncertainty concerning all
aspects of the decision making process. Moreover, opinions, goals,
constraints, etc. are usually imprecisely known. This makes the decision
making process difficult as one cannot employ conventional "hard" tools.