Fifty Years of Fuzzy Logic and its Applications pp 297-313 | Cite as

# Is the World Itself Fuzzy? Physical Arguments and Unexpected Computational Consequences of Zadeh’s Vision

## Abstract

Fuzzy methodology has been invented to describe imprecise (“fuzzy”) human statements about the world, statements that use imprecise words from natural language like “small” or “large”. Usual applications of fuzzy techniques assume that the world itself is “crisp”, that there are exact equations describing the world, and fuzziness of our statements is caused by the incompleteness of our knowledge. But what if the world itself is fuzzy? What if there is no perfect system of equations describing the physical world – in the sense that no matter what system of equations we try, there will always be cases when this system leads to wrong predictions? This is not just a speculation: this idea is actually supported by many physicists. At first glance, this is a pessimistic idea: no matter how much we try, we will never be able to find the the Ultimate Theory of Everything. But it turns out that this idea also has its optimistic aspects: namely, in this chapter, we show (somewhat unexpectedly), that if such a no-perfect-theory principle is true, then the use of physical data can drastically enhance computations.

## Notes

### Acknowledgments

This work was supported in part by the National Science Foundation grants HRD-0734825, HRD-124212, and DUE-0926721. The authors are thankful to the anonymous referees for valuable suggestions.

## Supplementary material

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