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Article #89Some thoughts on rationales for defeasible rules
From: Jeffrey S. Norman
Date: Fri, 08 Sep 1995 00:00
Date: Fri, 08 Sep 1995 00:00
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3264 bytes
Since this group seems dead, I am going to add my very meager voice to the din to see if anybody is really out there -- If a >- h means "a is reason for concluding b" and (a1 a2 a3 ... an) >- h means the same thing for the vector (a1 ...) A defeasible rule is (a1 a2 a3 ... an) >- h, which for the limited purposes of this post, I'll call X. The "evidence" a0 a1 ... is the set of all observations within a well formed language, E. Now, a rule has attributes, A(X). For example, a rule that prohibits the public display of campaign signs in residential areas might be described as: (i) restricting the volume of political expression in residential areas, (ii) making residential areas less "cluttered", or (iii) a property use regulation. The first attribute is descriptive/observed or computed. The second attributes attribute is a "purpose" for the rule. The third attribbute is more descriptive/categorical. There are obviously numerous attributes and even different type of attributes for a given rule. We can also imagine "rules about rules" that involve reasoning about rules using attributes. If X* is the set of all rules, and A*(X*) is the set of all attributes within the rule system X*, then a rule about rules takes as antecedents some subset of A*(X*), and as a consequent some element of X* or its negation. E.g., (b0 b1 b2 ... bn) >- G where bi is an element of A*(X*), and G is an element of X*. Okay. Now, is A*(X*) a subset of E? Similarly, is X* a subset of X? A superset? Neither? Note that in rule-formation, the rule maker often refers to hypothetical "results" of a rule under consideration, and in articulating "purpose" also may refer to actual "wrongs" that the rule is supposed to correct. These are rationales for a rule. The question is whether reasoning with these rationales about the rules themselves is any different than other reasoning, and how. Just a thought. -- --------------------------------------------------------------------------- Jeffery S. Norman, Esq. | Direct dial: (312) 755-2502 Foley & Lardner | Fax: (312) 755-1925 One IBM Plaza, Suite 3300 | 330 North Wabash Ave. | email: norman@interaccess.com Chicago, Illinois 60611 | --------------------------------------------------------------------------- COPYRIGHT NOTICE: The statements contained in this message are the property of Jeffery S. Norman, (C) Copyright 1995. Notwithstanding any express or implied license to the contrary, Microsoft Network is prohibited from distributing, redistributing, posting, duplicating or using this message, or any part thereof, without the author's express written consent. ___________________________________________________________________________
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X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 110176,bcc603a4b2ae0fe4,start X-Google-Attributes: gid110176,public From: norman@thymaster.interaccess.com (Jeffrey S. Norman) Subject: Some thoughts on rationales for defeasible rules Date: 1995/09/08 Message-ID: <42poho$mne@nntp.interaccess.com> X-Deja-AN: 109755008 organization: InterAccess, Chicago's best Internet service provider. reply-to: norman@interaccess.com newsgroups: chi.ai