In terms of logic, there is no contradiction here. Whatever contradiction there may appear to be is due to the use of the word "possible" in these statements. "It is not possible that Q" is equivalent simply to "not Q". "It is possible that Q" is equivalent simply to "Q or not Q". "Not Q" and "Q or not Q" do not contradict each other; the set of states corresponding to "not Q" is simply a subset of the set of states corresponding to "Q or not Q".
Shivani On Tue, 12 Jul 2005 [EMAIL PROTECTED] wrote: > Consider the following line of reasoning. Let p be the proposition > "Ronald was born in New York." From p, we can infer q: Ronald was born > in the United States. From q, we can infer r: It is possible that Ronald > was born in New Jersey. On the other hand, from p we can infer s: It is > not possible that Ronald was born in New Jersey. We have arrived at a > contradiction. What is wrong? Note: To answer the question, familiarity > with modal logic is not needed. > > -- > Lotfi A. Zadeh > Professor in the Graduate School, Computer Science Division > Department of Electrical Engineering and Computer Sciences > University of California > Berkeley, CA 94720 -1776 > Director, Berkeley Initiative in Soft Computing (BISC) > Tel.(office): (510) 642-4959 > _______________________________________________ > uai mailing list > uai@ENGR.ORST.EDU > https://secure.engr.oregonstate.edu/mailman/listinfo/uai > _______________________________________________ uai mailing list uai@ENGR.ORST.EDU https://secure.engr.oregonstate.edu/mailman/listinfo/uai
