In article <9l818o$36a$4@fbi-news.cs.uni-dortmund.de>, Stephan Lehmke <Stephan.Lehmke@cs.uni-dortmund.de> wrote:> In article <23af61c2.0108122107.6f0e7aab@posting.google.com>, Robert Dodier writes:
>> Consider the mayor of Ashtabula. Let A = "mayor's right eye is blue". >> Let B = "mayor's left eye is blue". Let B' = "mayor's left eye is brown". >> What do you suppose is the truth value of A B ? What about A B' ?
> Maybe I'm missing something here.
> Could you again, with rigorous logical notation, state this problem, > and point out the difference with two-valued logic?
>> The difficulty is that rules of the kind applied in fuzzy logic >> ignore relations between the elements of a compound proposition.
> What about two-valued logic?
It does not give any problems, looked at carefully. Probability is NOT a truth value system, and does not pretend to be so. In a truth value system, the truth of a compound proposition follows from that of the simple propositions involved. Probabilities have to be exist for all compounds simultaneously. If one starts with the fuzzy idea and adds this, probability is what will result. -- This address is for information only. I do not claim that these views are those of the Statistics Department or of Purdue University. Herman Rubin, Dept. of Statistics, Purdue Univ., West Lafayette IN47907-1399 hrubin@stat.purdue.edu Phone: (765)494-6054 FAX: (765)494-0558