Approximate Reasoning Methods in Vagueness: Graded and Rough Consequences.

this paper in to focus on one basic notion in some of these logics viz. the notion of consequence. This is not only basic notion of any logic but is at the root of any kind of inferential procedure, any kind of decision making. In the presence of vague concepts in the language, the notion of consequence is also considered to be vague, in general. What is the meaning of a vague consequence? Can there be any kind of "logic" with a kind of procedure that can be called vague in some sense? Rough consequence has been introduced and in studied [3]. We shall explain in some following section, in what sense the notion of rough consequence can be called "vague". The notion of graded consequence was proposed in [4]. In this report we would present some of the features of this notion and shall explain how does this notion address the issue of vagueness. Comparison of these two kinds of consequences will naturally peep into the mind. But that will be a future topic of study, though readers will notice that it has entered the discussion from time to time. 2 Graded consequenc