Another perspective on Default Reasoning
<|reference_start|>Another perspective on Default Reasoning: The lexicographic closure of any given finite set D of normal defaults is defined. A conditional assertion "if a then b" is in this lexicographic closure if, given the defaults D and the fact a, one would conclude b. The lexicographic closure is essentially a rational extension of D, and of its rational closure, defined in a previous paper. It provides a logic of normal defaults that is different from the one proposed by R. Reiter and that is rich enough not to require the consideration of non-normal defaults. A large number of examples are provided to show that the lexicographic closure corresponds to the basic intuitions behind Reiter's logic of defaults.<|reference_end|>
@article{lehmann2002another,
    title={Another perspective on Default Reasoning},
    author={Daniel Lehmann},
    journal={Annals of Mathematics and Artificial Intelligence, 15(1) (1995)
  pp. 61-82},
    year={2002},
    number={Leibniz Center for Research in Computer Science TR-92-12, July 1992},
    archivePrefix={arXiv},
    eprint={cs/0203002},
    primaryClass={cs.AI}
}