We consider how non-numeric linguistic variables may take their values from a pre-ordered set of vaguely defined linguistic terms. The mathematical structures that arise from the assumption that linguistic terms are pair-wise tolerant are considered. A homomorphism between tolerance spaces, filter bases and fuzzy numbers is shown. A proposal for modelling non-numeric linguistic variables with an ordered set of fuzzy numbers is introduced.
Jon WilliamsN. C. SteeleHelen Robinson