This is a survey about the title question, written for people who (like the author) see logic as forbidding, esoteric, and remote from their usual concerns. Beginning with a crash course on Zermelo-Fraenkel set theory, it discusses oracle independence; natural proofs; independence results of Razborov, Raz, DeMillo-Lipton, Sazanov, and others; and obstacles to proving P vs. NP independent of str...

In 6, 7], we presented syntactic characterizations and algorithms for computing the result of updating and revising a logical database under various approaches proposed in the literature. In this paper we focus on the design of versions of these algorithms able to provide an approximate answer if interrupted before completion. We use the PMA approach to update 18] as the main example, but the r...

despite the often false impression that the analytic philosophy as an anti-metaphysical movement has nothing to do with metaphysics, there can be found good reasons to grant the metaphysical dispositions of analytic philosophers, and thereby, to minimize the anti-metaphysical nature of analytic philosophy in its all phases. since analytic philosophy is a historical movement the main nature of w...

The present paper describes a MAC protocol for a high-speed ring with multiple tokens. The purpose of this protocol is to increase the throughput and to improve the delay-throughput characteristic of high-speed token-rings. The main concept of the new MAC protocol is to maintain several logical token-rings in the single physical ring. Each logical ring has its own token, and its operation is cl...

The question I am interested in in this paper is "How do words obtain their meanings?" The author I shall ask for help in answering this question is Gottlob Frege. This may appear surprising, since Frege is known as not being interested in the question posed. Frege wanted to provide mathematics with solid foundations. To achieve this, he aimed at constructing from scratch logical systems that m...

Current theorizing and evidence suggest that parenting stress might be greater among parents from both low and high socioeconomic positions (SEP) compared with those from intermediate levels because of material hardship among parents of low SEP and employment demands among parents of high SEP. However, little is known about how this socioeconomic variation in stress relates to the support that ...

Introduction: In 2009, deep-hole structures were discovered in the Moon’s Marius Hills (Fig.1), Mare Tranquillitatis, and Mare Ingenii in the images acquired by the SELENE cameras aboard Japan’s Selenological and Engineering Explorer (SELENE, nicknamed KAGUYA). They were very similar to several pits on Mars that were discovered in 2007 and reported as possible “skylights” opened on subsurface v...

Investigation performed at the University of Southern California Orthopaedic Surgery Associates, Keck School of Medicine, Los Angeles, California, Unlimited Research, San Antonio, Texas, Triangle Orthopaedic Associates, Durham, North Carolina, Orthopaedic Center of Vero Beach, Vero Beach, Florida, OrthoIndy, Indianapolis, Indiana, TRIA Orthopaedic Center, Bloomington Minnesota, and Greater Ches...

This study examines how parents of family and nonfamily abducted children cope with stress due to the disappearance of their child. The results show that all parents experience distress, regardless of whether it was a family or nonfamily abduction. Associated with parental distress are factors such as prior family stress, age of the child, recovery status of the child, and measures of social su...

The question I am interested in in this paper is "How do words obtain their meanings?" The author I shall ask for help in answering this question is Gottlob Frege. This may appear surprising, since Frege is known as not being interested in the question posed. Frege wanted to provide mathematics with solid foundations. To achieve this, he aimed at constructing from scratch logical systems that m...