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## Re: [ontolog-forum] Toward the logic of everyday reasoning

 To: "[ontolog-forum]" zadeh@xxxxxxxxxxxxxxxxx Adrian Walker Sat, 21 Nov 2009 10:28:12 -0500 <1e89d6a40911210728k354873cek75188297923e6826@xxxxxxxxxxxxxx>
 Hi Lofti, John & All  --Thanks for an illuminating discussion, and for the pointer to Lofti's most interesting paper.Lofti wrote to John:I would like to see your solutions [to]      1. Most Swedes are tall.        Most tall Swedes are blond.        Magnus is a Swede (picked at random)        What is the probability that Magnus is blond?     2. Usually it takes Robert about an hour to get home from work.         Usually Robert leaves office at about 5 pm__        What is the probability that Robert is home at 6:l5 pm?There's actually a direct way to do everyday reasoning of this kind.  You can do it in executable** English as follows. some-person is a Swedish national it is very likely that that-person is tall----------------------------------------------------- it is likely that that-person is blondsome-person is a Swedish national --------------------------------------------------------it is very likely that that-person is tallthis-person is a Swedish national ========================== Magnus(The single dotted line indicates a syllogism-like rule, the double line indicates a table of facts.)For Lofti's second example, you can write the following. usually, some-person leaves work about some-timewith probability some-prob that-person can take some-approx-number hour(s) to get home that-time + that-approx-number = some-arrival-time -------------------------------------------------------------------------------------------------------the probability that that-person gets home at that-arrival-time (with decimal part of hour) is that-prob it usually takes this-person about this-number hour(s) to get home===================================================================                        Robert                        1 usually, this-person leaves work about this-time=================================================                Robert                                     5 it usually takes some-person about some-number hour(s) to get homethe usual number of commuting hours varies by some-amount with probability some-probthat-number + that-amount = some-approx-number------------------------------------------------------------------ with probability that-prob that-person can take that-approx-number hour(s) to get homethe usual number of commuting hours varies by some-amount with probability some-prob==================================================================                                                                            -0.25                                             0.1                                                                             0                                                  0.2                                                                             0.25                                             0.5You can view, run and change these examples by visiting www.reengineeringllc.com and selecting Zadeh1 or Zadeh2.  You can also get step-by step English explanations (aka proofs) of the answers to the questions. Apologies to folks who have seen these kinds of examples before, and thanks for comments.                              -- Adrian                   Internet Business LogicA Wiki and SOA Endpoint for Executable** Open Vocabulary English over SQL and RDF Online at www.reengineeringllc.com    Shared use is freeAdrian WalkerReengineeringOn Fri, Nov 20, 2009 at 5:21 PM, John F. Sowa wrote: The following thread from the email forum for the Berkeley Initiative in Soft Computing (BISC) is related to the recent thread on "new logic" in ontolog forum. The first note is by Lotfi Zadeh.  Following that is a response by me, a response by LZ, and another note by me. John Sowa ********************************************************************* Subject: [bisc-group] Toward the logic of everyday reasoning Date: Tue, 17 Nov 2009 17:47:35 -0800 From: Lotfi A. Zadeh To: Bisc-Group , in FLu membership functions are not specified--they are perception-based. In FLu, there are no formal definitions, no formal theorems and no formal proofs. In this respect, unprecisiated fuzzy logic is similar to everyday reasoning. A model of FLu is f-geometry. In f-geometry, figures are drawn by hand with a spray pen. One essential difference between unprecisiated fuzzy logic and all existing logical systems is that FLu is a quasi-mathematical rather than a mathematical theory. What this suggests is a sobering thought that to achieve decisive success in formalization of everyday reasoning and mechanization of natural language understanding, it may be necessary to break away not just from existing logical systems but, more fundamentally, leave the realm of mathematics--the core of science--and explore the uncharted territory of quasi-mathematics.    Warm regards to all.                             Lotfi    Comments are welcome ********************************************************************* Dear Lotfi, I strongly agree with that point:  > But as we move further into the age of machine intelligence  > and automated decision-making, the need for a formalization  > of everyday reasoning and mechanization of natural language  > understanding will become increasingly apparent. But I'd like to emphasize some other points:  1. There is a continuum between scientific reasoning and everyday     reasoning.  The great breakthroughs in science in the 17th and     18th centuries used data gathered by the naked eye (Kepler) or     experiments that could be performed in the kitchen (Lavoisier).  2. The primary difference in the kind of logic needed for any     application depends primarily on the subject matter.  Some     subjects are naturally discrete and some are continuous.  3. Different reasoning methods and paradigms arise with     various language games in a Wittgensteinian sense, and     those paradigms may have different ontologies, different     kinds of logic, and different ways of using any particular     logic (e.g., induction, deduction, abduction, and analogy). For example, consider the games of chess, bridge, and baseball. Children learn to play the games through examples and minimal instruction.  They use their everyday methods of reasoning. But the logic used for chess is a very strict, two valued FOL. In principle, the best move in chess is completely determined. Yet even the fastest supercomputers need to use heuristics because the amount of computation grows exponentially with the depth of search. Bridge illustrates other points that require different methods of reasoning.  In principle, the game is deterministic for "double dummy" play, in which all four hands are visible.  But in normal play, critical information is missing, and the language of bidding and the signals during the play are extremely ambiguous. Probability and subtle inferences (especially negative inferences from what was *not* said or done) make the difference between an amateur and a world champion. Baseball is a curious mixture of a burst of continuous activity followed by a stopping point with a discrete evaluation:  ball or strike; fair or foul; safe or out; base hit or error.  All that continuous activity, classified by fuzzy perceptions, is recorded as a box score of discrete results.  > Imperfect information is information which in one or more respects  > is imprecise, uncertain, incomplete, unreliable, vague or partially  > true. That is certainly true of all three of these games and many other situations and activities in both science and in everyday life.  > First order logic and fuzzy logic are complementary rather  > than competitive. I would agree.  But the criteria for determining which kind of logic is needed depends on the subject matter and the kinds of applications, independent of the location of those subjects and applications -- in a home, a research laboratory, a hospital, a business, a courtroom, or a ballpark.  > I would like to see your solutions.  >  >  1. Most Swedes are tall.  >     Most tall Swedes are blond.  >     Magnus is a Swede (picked at random)  >     What is the probability that Magnus is blond?  >  >  2. Usually it takes Robert about an hour to get home from work.  >     Usually Robert leaves office at about 5 pm__  >     What is the probability that Robert is home at 6:l5 pm? Those are problems taken out of context.  I have often had students or clients come to me with problems taken out of context.  And I wouldn't try to solve them as stated.  I always ask:  Why do you want to know?  What would you do with the information? An excellent example is the subway braking system.  The goal was not to derive some kind of fuzzy estimate, but to design a smoother, more efficient braking system.  The application of fuzzy techniques was a means to an end, not the end in itself. To relate this to the questions about tall Swedes or Robert's arrival, I would have to ask a more fundamental question:  "Why do you ask?" John _________________________________________________________________ Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/ Config Subscr: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/ Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx Shared Files: http://ontolog.cim3.net/file/ Community Wiki: http://ontolog.cim3.net/wiki/ To join: http://ontolog.cim3.net/cgi-bin/wiki.pl?WikiHomePage#nid1J To Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx ``` _________________________________________________________________ Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/ Config Subscr: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/ Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx Shared Files: http://ontolog.cim3.net/file/ Community Wiki: http://ontolog.cim3.net/wiki/ To join: http://ontolog.cim3.net/cgi-bin/wiki.pl?WikiHomePage#nid1J To Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx    (01) ```
 Current Thread [ontolog-forum] Toward the logic of everyday reasoning, John F. Sowa Re: [ontolog-forum] Toward the logic of everyday reasoning, Adrian Walker <= Re: [ontolog-forum] Toward the logic of everyday reasoning, John F. Sowa Re: [ontolog-forum] Toward the logic of everyday reasoning, Paola Di Maio