While ecological resilience may explain why apparent symptoms of desertification are often temporary, social resilience can prevent degradation resulting from overexploitation of land in response to drought and other constraints. This paper describes a Social Resilience Model in which actors switch from performance strategies to survival strategies when the perceived severity of constraints exceeds a critical performance-survival threshold (PST). This is determined in comparison with a reference mode that depends on a learning facility developed by repeated exposure to cycles of constraint, search and feedback. Actors select particular strategies by comparing welfare gains with their aspiration levels-a concept that allows more flexible decision making than profit maximizing or satisficing alone. The model is tested in the silvopastoral zone of Senegal, where desertification is not as widespread as commonly assumed, despite severe constraints. The two major ethnic groups, the Wolof (mainly croppers) and the Peul (mainly pastoralists) anticipate and respond to environmental and socio-economic constraints differently, and have different performance and survival strategies. The Peul have the higher social resilience, with more flexible decision-making objectives, greater mobility, a more extensive action space, a learning facility supporting efficient search and feedback processes, a reference mode attuned to high anticipation and recognition of stress, and a high PST. They also exhibit more continuous performance-survival switching than the Wolof, who make a radical change from cropping to labour migration and reliance on external support.

Many who take a dismissive attitude towards metaphysics trace their view back to Carnap's 'Empiricism, Semantics and Ontology' (1950a). But the reason Carnap takes a dismissive attitude to metaphysics is a matter of controversy. I will argue that no reason is given in 'Empiricism, Semantics and Ontology', and this is because his reason for rejecting metaphysical debates was given in 'Pseudo-Problems in Philosophy ' (1928). The argument there assumes verificationism, but I will argue that his argument survives the rejection of verificationism. The root of his argument is the claim that metaphysical statements cannot be justified; the point is epistemic, not semantic. I will argue that this remains a powerful challenge to metaphysics that has yet to be adequately answered.

What does logic tells us how about we ought to reason? If P entails Q, and I believe P, should I believe Q? I will argue that we should embed the issue in an independently motivated contextualist semantics for ‘ought’, with parameters for a standard and set of propositions. With the contextualist machinery in hand, we can defend a strong principle expressing how agents ought to reason while accommodating conflicting intuitions. I then show how our judgments about blame and guidance can be handled by this machinery.

An attractive picture of the world is that some features are metaphysically fundamental and others are derivative, with the derivative features grounded in the fundamental features. But how do we have justified beliefs about which features are fundamental? What is the epistemology of fundamentality? I sketch a response in this paper. The guiding idea is that the same properties cause the same experiences. I argue that a probabilistic connection between epistemic fundamentality and metaphysical fundamentality is sufficient for justified beliefs about the metaphysically fundamental.

An important line of response to scepticism appeals to the best explanation. But anti-sceptics have not engaged much with work on explanation in the philosophy of science. I plan to investigate whether plausible assumptions about best explanations really do favour anti-scepticism. I will argue that there are ways of constructing sceptical hypotheses in which the assumptions do favour anti-scepticism, but the size of the support for anti-scepticism is small.