Social networks play a significant role in learning and thus in farmers’ adoption of new agricultural technologies. This study examined the effects of social network factors on information acquisition and adoption of new seed varieties among groundnut farmers in Uganda and Kenya. The data were generated through face-to-face interviews from a random sample of 461 farmers, 232 in Uganda and 229 in Kenya. To assess these effects two alternative econometric models were used: a seemingly unrelated bivariate probit model and a (...) recursive bivariate probit model. The statistical evaluation of the SUBP shows that information acquisition and adoption decisions are interrelated while tests for the RBP do not support this latter model. Therefore, the analysis is based on the results obtained from the SUBP. These results reveal that social network factors, particularly weak ties with external support, partially influence information acquisition, but do not influence adoption. In Uganda, external support, gender, farm size, and geographic location have an impact on information acquisition. In Kenya, external support and geographic location also have an impact on information acquisition. With regard to adoption, gender, household size, and geographic location play the most important roles for Ugandan farmers, while in Kenya information from external sources, education, and farm size affect adoption choice. The study provides insight on the importance of external weak ties in groundnut farming, and a need to understand regional differences along gender lines while developing agricultural strategies. This study further illustrates the importance of farmer participation in applied technology research and the impact of social interactions among farmers and external agents. (shrink)

This volume is devoted to Lewis's work in ethics and social philosophy. Topics covered include the logic of obligation and permission; decision theory and its relation to the idea that beliefs might play the motivating role of desires; a subjectivist analysis of value; dilemmas in virtue ethics; the problem of evil; problems about self-prediction; social coordination, linguistic and otherwise; alleged duties to rescue distant strangers; toleration as a tacit treaty; nuclear warfare; and punishment. This collection, and the two preceding volumes, (...) will disseminate more widely the work of an eminent and influential contemporary philosopher. (shrink)

David Kellogg Lewis (1941-2001) was one of the most influential philosophers of the twentieth century. He made significant contributions to almost every area of analytic philosophy including metaphysics, philosophy of language, philosophy of mind, and philosophy of science, and set the agenda for various debates in these areas which carry on to this day. In several respects he remains a contemporary figure, yet enough time has now passed for historians of philosophy to begin to study his place in twentieth (...) century thought. His philosophy was constructed and refined not just through his published writing, but also crucially through his life-long correspondence with fellow philosophers, including leading figures such as D.M. Armstrong, Saul Kripke, W.V. Quine, J.J.C. Smart, and Peter van Inwagen. His letters formed the undercurrent of his published work and became the medium through which he proposed many of his well-known theories and discussed a range of philosophical topics in depth. A selection of his vast correspondence over a 40-year period is presented here across two volumes. The letters offer an organic story of the origins, development, breadth, and depth of his philosophy in its historical context, as well as a glimpse into the influence of his many interlocutors."-- OCLC OLUC. (shrink)

This book is a defense of modal realism; the thesis that our world is but one of a plurality of worlds, and that the individuals that inhabit our world are only a few out of all the inhabitants of all the worlds. Lewis argues that the philosophical utility of modal realism is a good reason for believing that it is true.

This volume is devoted to Lewis's work in metaphysics and epistemology. Topics covered include properties, ontology, possibility, truthmaking, probability, the mind-body problem, vision, belief, and knowledge. The purpose of this collection, and the volumes that precede and follow it, is to disseminate more widely the work of an eminent and influential contemporary philosopher. The volume will serve as a useful work of reference for teachers and students of philosophy.

Counterfactuals is David Lewis' forceful presentation of and sustained argument for a particular view about propositions which express contrary to fact conditionals, including his famous defense of realism about possible worlds and his theory of laws of nature.

Topics in Cognitive Science, Volume 13, Issue 1, Page 128-141, January 2021.

This is the second volume of philosophical essays by one of the most innovative and influential philosophers now writing in English. Containing thirteen papers in all, the book includes both new essays and previously published papers, some of them with extensive new postscripts reflecting Lewis's current thinking. The papers in Volume II focus on causation and several other closely related topics, including counterfactual and indicative conditionals, the direction of time, subjective and objective probability, causation, explanation, perception, free will, and rational (...) decision. Throughout, Lewis analyzes global features of the world in such a way as to show that they might turn out to supervene on the spatiotemporal arrangement of local qualities. (shrink)

Christianity teaches that whenever evil is done, God had ample warning. He could have prevented it, but He didn't. He could have stopped it midway, but He didn't. He could have rescued the victims of the evil, but - at least in many cases - He didn't. In short, God is an accessory before, during, and after the fact to countless evil deeds, great and small. An explanation is not far to seek. The obvious hypothesis is that the Christian God (...) is really some sort of devil. Maybe He is a devil as popularly conceived, driven' by malice. Or maybe He is unintelligibly capricious. Or maybe He is a fanatical artist who cares only for the aesthetic quality of creation - perhaps the abstract beauty of getting rich variety to emerge from a few simple laws, or perhaps the concrete drama of human life with all its diversity - and cares nothing for the good of the creatures whose lives are woven into His masterpiece. Oust as a tragedian has no business providing a happy end out of compassion for his characters.) But no; for Christianity also teaches that God is morally perfect and perfectly benevolent, and that He loves all of His creatures; and that these things are true in a sense not a million miles from the sense in which we attribute morality, benevolence, or love to one another. (shrink)

This is the first of a three-volume collection of David Lewis's most recent papers in all the areas to which he has made significant contributions. The purpose of this collection (and the two volumes to follow) is to disseminate even more widely the work of a preeminent and influential late twentieth-century philosopher. The papers are now offered in a readily accessible format. This first volume is devoted to Lewis's work on philosophical logic from the last twenty-five years. The topics (...) covered include: deploying the methods of formal semantics from artificial formalised languages to natural languages, model-theoretic investigations of intensional logic, contradiction, relevance, the differences between analog and digital representation, and questions arising from the construction of ambitious formalised philosophical systems. The volume will serve as an important reference tool for all philosophers and their students. (shrink)

If a guilty offender is justly sentenced to be punished and an innocent volunteer agrees to be punished instead, is that any reason to leave the offender unpunished? In the context of mundane criminal justice, we mostly think not. But in a religious context, some Christians do believe in penal substitution as a theory of the atonement. However, it is not just these Christians, but most of us, who are of two minds. If the punishment is an imprisonment or death, (...) we do not believe in penal substitution. But if it’s a fine, even a big fine, we mostly do. (shrink)

Common formulations of the principle of charity in translation seem to undermine attributions of irrationality in social scientific accounts that are otherwise unexceptionable. This I call the problem of irrationality. Here I resolve the problem of irrationality by developing two complementary views of the principle of charity. First, I develop the view (ill-developed in the literature at present) that the principle of charity is preparatory, being needed in the construction of provisional first-approximation translation manuals. These serve as the basis for (...) explanatory accounts and associated refinements in the translation manual. In developing such explanatory accounts, the principle of charity is no longer constraining. Thus, the principle of charity applies only in the early stages of constructing translation manuals, and there is no problem of irrationality in the later stages of constructing translation manuals. Second, I reduce the principle of charity, where it does apply, to a special case of what I call the principle of explicability: so translate as to attribute explicable beliefs and practices to the speakers of the source-language. I show that the appropriate formulation of the principle of charity counsels just what the principle of explicability requires in the early stages of social scientific investigation. (shrink)

The Simple View (SV) holds that for someone to intentionally A, he must intend to A. Critics of SV point to intentional actions which, due to belief-conditions or consistency constraints, agents cannot intend. By recognizing species of intention which vary according to the agent's confidence in acting, I argue that the stringency of consistency constraints depends on the agent's confidence. A more sophisticated SV holds that the species of intending is related to the degree of intentionality of the action. Finally, (...) I show that where agents do what they believe impossible, without intending to do so, the action is not intentional. (shrink)

It is advisable to treat some sorts of discourse about fiction with the aid of an intensional operator "in such-And-Such fiction...." the operator may appear either explicitly or tacitly. It may be analyzed in terms of similarity of worlds, As follows: "in the fiction f, A" means that a is true in those of the worlds where f is told as known fact rather than fiction that differ least from our world, Or from the belief worlds of the community in (...) which the fiction originated. (shrink)

The mammalian blastocyst exhibits a high capacity for aerobic glycolysis, a metabolic characteristic of tumours. It has been considered that aerobic glycolysis is a means to ensure a high carbon flux to fulfil biosynthetic demands. Here, alternative explanations for this pattern of metabolism are considered. Lactate creates a microenvironment of low pH around the embryo to assist the disaggregation of uterine tissues to facilitate trophoblast invasion. Further it is proposed that lactate acts as a signalling molecule (especially at the reduced (...) oxygen tension present at implantation) to elicit bioactive VEGF recruitment from uterine cells, to promote angiogenesis. Finally it is suggested that the region of high lactate/low pH created by the blastocyst modulates the activity of the local immune response, helping to create immune tolerance. Consequently, the mammalian blastocyst offers a model to study the role of microenvironments, and how metabolites and pH are used in signalling. (shrink)

Epistemology has recently come to more and more take the articulate form of an investigation into how we do, and perhaps might better, manage the cognitive chores of producing, modifying, and generally maintaining belief-sets with a view to having a true and systematic understanding of the world. While this approach has continuities with earlier philosophy, it admittedly makes a departure from the tradition of epistemology as first philosophy.

(1984). The projection argument in Galileo and Copernicus: Rhetorical strategy in the defence of the new system. Annals of Science: Vol. 41, No. 2, pp. 109-133.