Michio SUGENO

Emeritus Professor at Tokyo Institute of Technology, Emeritus Researcher at European Centre for Soft Computing

Wednesday 20th – 14h00-15h00

What Kinds of Uncertainty Are We Aware of? − Categories and Modalities of Uncertainty −

As a conventional concept of uncertainty, we are familiar with the ‘probability’ of a phenomenon. Also we often discuss the ‘uncertainty’ of knowledge. Recently, Fuzzy Theory has brought a hidden uncertainty, ‘fuzziness’, to light. Reflections on these ideas lead to a fundamental question: What kinds of uncertainty are we aware of? Motivated by this question, this study aims to explore categories and modalities of uncertainty. For instance, we have found that (i) ‘form’ is a category of uncertainty; (ii) ‘inconsistency’ is a modality of uncertainty; (iii) the inconsistency of form is one of the major uncertainties. We elucidate seven uncertainties (or nine if subcategories are counted) and identify three essential ones among them, such as the fuzziness of words. We also discuss some linguistic and logico-philosophical issues concerning uncertainty. Finally, the structure of uncertainty will be shown.