Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uwm.edu!linac!pacific.mps.ohio-state.edu!zaphod.mps.ohio-state.edu!usc!ucla-cs!ucivax!cain From: cain@ics.uci.edu (Timothy Cain) Newsgroups: comp.ai Subject: Re: Abductive Reasoning Message-ID: <2821CDCD.1144@ics.uci.edu> Date: 3 May 91 20:53:32 GMT References: <1991May3.181328.16368@cs.ubc.ca> Organization: UC Irvine Department of ICS Lines: 44 In <1991May3.181328.16368@cs.ubc.ca> kean@cs.ubc.ca (Alex Kean) writes: >After working on so call "abductive reasoning" for a while, I am >beginning to wonder about the meaning of the term "abductive >reasoning" and its historical reason for such name. From Webster, [ definition deleted ] First, let me say that my New Webster's dictionary includes the definition "in logic, a syllogism, the minor premise and conclusion of which are only probable" Not exactly what I call abduction, but closer the anatomical definition! >and "abductive" is not found in the dictionary. I always thought of >"abductive reasoning" as a form of reasoning that explain its >conclusion, i.e. provides the proofs as an answer rather that just >yes/no answer. Forming a complete proof (all of the leaves of the proof are known to be true) is a deductive process, not an abductive one. Abduction provides a plausible proof, where one or more of the leaves of the proof are not known to be true (or at least, their certainty is not 100%). If any proof of a known conclusion requires the reasoner to make an assumption, that's a good sign that abductive reasoning is being used. A lot of people say Sherlock Holmes performed deduction, but I disagree. He made MANY assumptions to back up his conclusions, which is an abductive process (or at the very least, it's assumptive deduction, but that's a whole new can of worms!). >I realized the word "abduction" was coined by Charles Sanders Peirce >(1839-1914) but I am unable to understand his choice of using the term. Good question. Maybe the latin root? >Best Regards, >Alex Kean -- Timothy D. Cain Department of Information and Computer Science UC Irvine cain@ics.uci.edu (ARPA)