## Notre Dame Journal of Formal Logic

### Constructive Modelings for Theory Change

#### Abstract

Alchourrón, Gärdenfors and Makinson have developed and investigated a set of rationality postulates which appear to capture much of what is required of any rational system of theory revision. This set of postulates describes a class of revision functions, however it does not provide a constructive way of defining such a function. There are two principal constructions of revision functions, namely an epistemic entrenchment and a system of spheres. We refer to their approach as the AGM paradigm. We provide a new constructive modeling for a revision function based on a nice preorder on models, and furthermore we give explicit conditions under which a nice preorder on models, an epistemic entrenchment, and a system of spheres yield the same revision function. Moreover, we provide an identity which captures the relationship between revision functions and update operators (as defined by Katsuno and Mendelzon).

#### Article information

Source
Notre Dame J. Formal Logic, Volume 36, Number 1 (1995), 120-133.

Dates
First available in Project Euclid: 19 December 2002

Permanent link to this document
https://projecteuclid.org/euclid.ndjfl/1040308831

Digital Object Identifier
doi:10.1305/ndjfl/1040308831

Mathematical Reviews number (MathSciNet)
MR1359110

Zentralblatt MATH identifier
0844.03017

#### Citation

Peppas, Pavlos; Williams, Mary-Anne. Constructive Modelings for Theory Change. Notre Dame J. Formal Logic 36 (1995), no. 1, 120--133. doi:10.1305/ndjfl/1040308831. https://projecteuclid.org/euclid.ndjfl/1040308831

#### References

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