This report draws on lessons learned from observations made at seven case study sites, all of which permit economic activities, especially recreation, that are not harmful to the biological values and natural functions of the area. There is now a need to translate these experiences into policy instruments. The guidelines, summarized in some 20 pages, offer sound and well-documented advice on how to proceed.

This handbook provides information on the business case for biodiversity, as well as current biodiversity issues for business, and guidance on corporate biodiversity strategies. The current status of the debate is illustrated by specific case stories, thus providing an opportunity for companies to highlight their renewed commitment to an issue of high importance. The accompanying CD-ROM provides additional biodiversity resources, including extended case studies and lists of the key institutions and sources of information that can help build a company’s capacity (...) for integrating biodiversity into business practice. (shrink)

Cieslinski has given an interesting response to Shapiro 1998 and Ketland 1999, which argued that deflationary truth theories are inadequate, since they lack the property of ‘reflective adequacy’. Cieslinski’s response, following Tennant (2002, 2005), aims to explain, without a detour using truth axioms, why someone who accepts the axioms of a theory should also accept its reflection principles. The argument is formulated very clearly (in fact, to justify a different reflection principle), and involves a couple of important assumptions, the crucial (...) one being that the reflection scheme for a theory ‘expresses’ the acceptance of its theorems. I argue that this assumption is incorrect. For if the reflection principle for a theory expresses the claim that one is ready to accept its theorems, this latter claim should imply the reflection principle. But it does not. So, I conclude, the response fails to yield the required ‘truth-free’ method for proving or justifying reflection principles. (shrink)

Neologicists have claimed that Hume's Principle (HP) may be taken as a stipulative definition of cardinal number. This claim is threatened by the fact that HP is not conservative over pure second-order logic. I argue that the dominant neologicist response to the conservativeness objection is not satisfactory. Then I propose a novel version of neologicism, based on Heck's Two-sorted Hume's Principle (2HP), which does meet the conservativeness objection—provided that conservativeness is understood semantically and not deductively. I also (...) argue that on my proposal, the Bad Company problem is solved by conservativeness. (shrink)

Truth is often considered to be a logico-linguistic tool for expressing indirect endorsements and infinite conjunctions. In this article, I will point out another logico-linguistic function of truth: to enable and validate what I call a blind argument, namely, an argument that involves indirectly endorsed statements. Admitting this function among the logico-linguistic functions of truth has some interesting consequences. In particular, it yields a new type of so-called conservativeness argument, which poses a new type of threat to deflationism about (...) truth. (shrink)

Many philosophers believe that a deflationist theory of truth must conservatively extend any base theory to which it is added. But when applied to arithmetic, it's argued, the imposition of a conservativeness requirement leads to a serious objection to deflationism: for the Gödel sentence for Peano Arithmetic is not a theorem of PA, but becomes one when PA is extended by adding plausible principles governing truth. This paper argues that no such objection succeeds. The issue turns on how we (...) understand the notion of logical consequence implicit in any conservativeness requirement, and whether we possess a categorical conception of the natural numbers. I offer a disjunctive response: if we possess a categorical conception of arithmetic, then deflationists have principled reason to accept a rich notion of logical consequence according to which the Gödel sentence follows from PA. But if we do not, then the reasons for requiring the derivation of the Gödel sentence lapse, and deflationists are free to accept a conservativeness requirement stated proof-theoretically. Either way, deflationism is in the clear. (shrink)

What philosophers have in mind when they think about vagueness are sorites cases. Unlike vague scientific or artificial expressions, however, vague natural language expressions do not display the kind of vagueness that we associate with the sorites; they rather display what I call cluster vagueness. A non-trivial consequence of this is that those legal definitions that state precisifications of natural language concepts not only add aspects of meaning to existing expressions but also effectively change the meanings of these expressions. From (...) this, in turn, it follows that we should avoid precisifying ordinary expressions with the help of legal definitions to the extent that we wish legal language to be in line with natural language. And being in line with natural language may help us to deal with gaps in our laws at the very moment we become aware of them, and not just afterwards. (shrink)

At the end of the nineties some authors (Leon Horsten, Stewart Shapiro and Jeffrey Ketland) worked out a fairly technical argument against deflationary theories of truth. In a nutshell, deflationism, it was argued, is committed to conservativeness by the the claim that truth is not a substantial notion, a conservative theory (under the light of certain logico-mathematical facts) can not be an adequate theory of truth, therefore deflationism is an inadequate theory of truth. Beside the apparent simplicity of this (...) argument, it hides a lot of subtle questions and problems and it is a very sophisticated argument. Deflationists attempted to reply in different ways to the argument but the general impression is that, so far, they have not been able to find a good solution. Deflationism does really seem to be condemned to be an inadequate theory. This work is divided in three main parts. The first part is a very general survey where the study of the notion of truth is introduced. In Chapter One we sketch philosophical theories of truth comparing more traditional approaches to deflationism; we briefly survey the history of deflationism and then we try to find a general characterization of it. In the second Chapter the notion of truth is considered under a formal approach and some important and simple axiomatic theories of truth are sketched. The second part join the philosophical and the formal approach to truth together into the debate over deflationism and conservativeness. In Chapter Three we introduce the notion of conservativeness and we give some example of its application both to logical and to philosophical matters. Then we spell out the argument from conservativeness and we discuss it in order to get a precise requirement that deflationary theories are supposed to satisfy. In Chapter Four we focus on deflationist replies to the argument from conservativeness and we discuss each solution. The third and last part is the core of the work, it consists in a more technical study of some presuppositions of the debate: we want to take a step backward and to compare the two major claims of deflationism - the centrality of T-sentences and the logical function of the truth predicate - with conservativeness. Many of the results used here are due to other logicians and philosophers and are available in literature yet, the originality consists in a critical consideration of such results under the light of the conservativeness of truth. More original reflections can be found in Chapter Seven and in particular in the conclusive Chapter Eight, where the proposal is completely new, at least as far as I know. In Chapter Five we compare T-sentences with the empty base theory and in Chapter Six we analyse in what measure a deflationary theory can be really conservative over a theory of syntax. The result would be quite serious for a deflationist. In Chapter Seven we compare conservativeness with the logical function of the truth predicate. We will get the unpleasant result that the truth predicate is not able to serve the logical function in no sense without loosing conservativeness at the same time. In Chapter Eight we draw some conclusion and we sketch a reformulation of the conservativeness requirement. This new requirement, we will argue, makes justice to the claim of the unsubstantiality of truth and at the same time it does not condemn deflationism to death. In this way, we will be able also to clarify what is the exact role of truth in sentential quantification, showing that this role is really innocent and unsubstantial. The unsubstantiality of deflationary truth, though, will not force deflationism into an inadequate theory of truth. (shrink)

My contribution to the symposium on Goedel’s philosophy of mathematics at the spring 2006 Association for Symbolic Logic meeting in Montreal. Provisional version: references remain to be added. To appear in an ASL volume of proceedings of the Goedel sessions at that meeting.

This introduction to biological conservation assesses the value judgments at the heart of conservation. The author elaborates on such questions as: how much habitat does an endangered species require?; does this particular species deserve to be saved?; who will pay for its upkeep?; and much more.

We formulate a Π1 sentence τ which is a version of the Tableau consistency of GlΔ0. The sentence τ is true and is provable in GlΔ0 + exp. We construct a model M of GlΔ0+Ω1+τ+BGs1 which has no proper end-extension to a model of GlΔ0+Ω1+τ. Also we prove that GlΔ0+Ω1+τ is not Π1 conservative over GlΔ0+τ.

Parents can benefit their offspring by conserving resources that the offspring stand to inherit. Thus, inheritance of resources should promote the evolution of propensities to conserve. But inheritance also has another, less obvious effect: it can reduce the fertility of the conserver’s grandchildren, thus reducing the expected number of great-grandchildren. Consequently, inheritance of resources promotes the evolution of conservation less than might be supposed.

Religious conservatives in the U.S. have frequently opposed public-health measures designed to combat STDs among minors, such as sex education, condom distribution, and HPV vaccination. Using Rawls’s method of conjecture, I will clear up what I take to be a misunderstanding on the part of religious conservatives: even if we grant their premises regarding the nature and source of sexual norms, the wide-ranging authority of parents to enforce these norms against their minor children, and the potential sexual-disinhibition effects of the (...) above public-health measures, their opposition to at least one of these measures, HPV vaccination, cannot be justified. In fact, their comprehensive doctrines, when properly interpreted, should lead them to back this measure and thereby draw closer to a policy consensus with other citizens regarding teenage sexual health. (shrink)

While there is a significant amount of discussion in philosophy on the ethics of wildlife conservation, there is relatively less discussion on the justice of conservation. By the “justice of conservation”, I mean the question of what we owe to fellow human beings with respect to conservation goals and practices. The goal of this paper is two-fold: first to highlight the justice-gap in the morality of wildlife conservation and, second, to frame and propose two dimensions of global conservational justice for (...) further discussion. Specifically, I suggest the need for a more equitable conservation to address the problem of distributive unfairness in global conservation practices, and the need to “decolonize” conservation to ensure more deliberative fairness in how global conservation problems and solutions are determined. (shrink)

Conservation biology emerged as an organized academic discipline in the United States in the 1980s though much of its theoretical framework was originally developed in Australia. Significant differences of approach in the two traditions were resolved in the late 1990s through the formulation of a consensus framework for the design and adaptive management of conservation area networks. This entry presents an outline of that framework along with a critical analysis of conceptual issues concerning the four theoretical problems that emerge from (...) it: (i) place prioritization for conservation action; (ii) the selection of surrogates for biodiversity in conservation planning; (iii) the assessment of vulnerability of conservation areas; and (iv) the synchronization of incommensurable criteria including socio-economic constraints on conservation planning. (shrink)

Deflationists argue that ‘true’ is merely a logico-linguistic device for expressing blind ascriptions and infinite generalisations. For this reason, some authors have argued that deflationary truth must be conservative, i.e. that a deflationary theory of truth for a theory S must not entail sentences in S’s language that are not already entailed by S. However, it has been forcefully argued that any adequate theory of truth for S must be non-conservative and that, for this reason, truth cannot be deflationary :493–521, (...) 1998; Ketland in Mind 108:69–94, 1999). We consider two defences of conservative deflationism, respectively proposed by Waxman :429–463, 2017) and Tennant :551–582, 2002), and argue that they are both unsuccessful. In Waxman’s hands, deflationists are committed either to a non-purely expressive notion of truth, or to a conception of mathematics that does not allow them to justifiably exclude non-conservative theories of truth. Tennant’s conservative deflationism fares no better: if deflationist truth must be conservative over arithmetic, it can be shown to collapse into a non-conservative variety of deflationism. (shrink)

We discuss two desirable properties of deflationary truth theories: conservativeness and maximality. Joining them together, we obtain a notion of a maximal conservative truth theory - a theory which is conservative over its base, but can't be enlarged any further without losing its conservative character. There are indeed such theories; we show however that none of them is axiomatizable, and moreover, that there will be in fact continuum many theories of this sort. It turns out in effect that the (...) deflationist still needs some additional principles, which would permit him to construct his preferred theory of truth. (shrink)

This paper shows how to conservatively extend classical logic with a transparent truth predicate, in the face of the paradoxes that arise as a consequence. All classical inferences are preserved, and indeed extended to the full (truth—involving) vocabulary. However, not all classical metainferences are preserved; in particular, the resulting logical system is nontransitive. Some limits on this nontransitivity are adumbrated, and two proof systems are presented and shown to be sound and complete. (One proof system allows for Cut—elimination, but the (...) other does not.). (shrink)

The Exclusion Argument for physicalism maintains that since (1) every physical effect has a sufficient physical cause, and (2) cases of causal overdetermination are rare, it follows that if (3) mental events cause physical events as frequently as they seem to, then (4) mental events must be physical in nature. In defence of (1), it is sometimes said that (1) is supported if not entailed by conservation laws. Against this, I argue that conservation laws do not lend sufficient support to (...) (1) to render its denial ‘unscientific’, and that those who accept (3) and deny (4) may consequently respond to the Exclusion Argument by denying (1) without thereby setting themselves at odds with current science. I also argue that conservation laws are compatible with (3) and the negation of (4), and that one can therefore accept conservation laws and (3) while denying both (1) and (4). (shrink)

We systematically study conservation theorems on theories of semi-classical arithmetic, which lie in-between classical arithmetic $\mathsf {PA}$ and intuitionistic arithmetic $\mathsf {HA}$. Using a generalized negative translation, we first provide a structured proof of the fact that $\mathsf {PA}$ is $\Pi _{k+2}$ -conservative over $\mathsf {HA} + {\Sigma _k}\text {-}\mathrm {LEM}$ where ${\Sigma _k}\text {-}\mathrm {LEM}$ is the axiom scheme of the law-of-excluded-middle restricted to formulas in $\Sigma _k$. In addition, we show that this conservation theorem is optimal in the (...) sense that for any semi-classical arithmetic T, if $\mathsf {PA}$ is $\Pi _{k+2}$ -conservative over T, then ${T}$ proves ${\Sigma _k}\text {-}\mathrm {LEM}$. In the same manner, we also characterize conservation theorems for other well-studied classes of formulas by fragments of classical axioms or rules. This reveals the entire structure of conservation theorems with respect to the arithmetical hierarchy of classical principles. (shrink)

Conservativeness has been proposed as an important requirement for deflationary truth theories. This in turn gave rise to the so-called ‘conservativeness argument’ against deflationism: a theory of truth which is conservative over its base theory S cannot be adequate, because it cannot prove that all theorems of S are true. In this paper we show that the problems confronting the deflationist are in fact more basic: even the observation that logic is true is beyond his reach. This seems (...) to conflict with the deflationary characterization of the role of the truth predicate in proving generalizations. However, in the final section we propose a way out for the deflationist — a solution that permits him to accept a strong theory, having important truth-theoretical generalizations as its theorems. (shrink)

_Conservative Reductionism_ sets out a new theory of the relationship between physics and the special sciences within the framework of functionalism. It argues that it is wrong-headed to conceive an opposition between functional and physical properties (or functional and physical descriptions, respectively) and to build an anti-reductionist argument on multiple realization. By contrast, (a) all properties that there are in the world, including the physical ones, are functional properties in the sense of being causal properties, and (b) all true descriptions (...) (laws, theories) that the special sciences propose can in principle be reduced to physical descriptions (laws, theories) by means of functional reduction, despite multiple realization. The book develops arguments for (a) from the metaphysics of properties and the philosophy of physics. These arguments lead to a conservative ontological reductionism. It then develops functional reduction into a fully-fledged, conservative theory reduction by means of introducing functional sub-types that are coextensive with physical types, illustrating that conservative reductionism by means of case studies from biology (notably the relationship between classical and molecular genetics). (shrink)

A conservation law in physics can be either a constraint on the kinds of interaction there could be or a coincidence of the kinds of interactions there actually are. This is an important, unjustly neglected distinction. Only if a conservation law constrains the possible kinds of interaction can a derivation from it constitute a scientific explanation despite failing to describe the causal/mechanical details behind the result derived. This conception of the relation between “bottom-up” scientific explanations and one kind of “top-down” (...) scientific explanation is motivated by several examples from classical and modern physics. (shrink)

This paper revisits the conservative thought of Shirley Robin Letwin, a key intellectual of the New Right and the LSE Right, as well as a prominent defender of Thatcherism. It situates Letwin within the intellectual milieu of the New Right, emphasising both her contributions to Thatcherite ideas and her broader defence of Thatcherite conservatism. Letwin’s political philosophy rests on a sceptical outlook shaped by Hume, Oakeshott, and Hobbes, rejecting rationalist and liberal universalism in favour of tradition, authority, and historical practice. (...) Central to her work is the concept of “conservative individualism”: a moral individualism embodied in the English gentleman as the exemplar of liberty in character. The paper examines her thought in relation to scepticism – exemplified in her critique of liberal rationalism – her defence of individuality, law and civil association, and her interpretation of Thatcherism as a project of moral restoration through the revival of the “vigorous virtues”. While acknowledging the limits of Letwin’s conservatism, the article argues that her account of conservative individualism not only illuminates the intellectual defence of Thatcherism but also retains contemporary resonance for understanding the enduring dilemmas of modern conservatism. (shrink)

The relation between divine and human agency is a topic of considerable interest in its own right, but this chapter’s present interest in it is fueled by what seems an unsettling parallel between divine conservation and theological determinism. This chapter addresses the problem that (a) divine conservation occasions a threat to human free agency that is as bad as, and potentially worse than, the threat to it that emanates from theological determinism, and (b) whereas the thesis of theological determinism is (...) optional for theists, the doctrine of divine conservation is not optional for theists (as opposed to philosophical deists). The aim of the chapter is to develop a model in which free agency is compossible with a robust view of divine conservation, but which does not also render free agency compatible with theological determinism. (shrink)

A conservative and a liberal approach to psychiatry can both seek philosophical foundations in David Hume. The conservative approach takes inspiration from Hume's emphasis on custom, such as in relation to the problem of inductive reasoning. Too much deviation from custom is evidence of madness. The liberal approach takes inspiration from the Humean conception of rationality as exclusively concerned with the means taken to ends, not the ends themselves. A man who departs from custom in what seem to be excessive (...) ways may nevertheless count as rational, given his ends in life, such as Hume's end of enduring literary fame. (shrink)