In the years following its publication, F.A. Hayek's pioneering work on business cycles was regarded as an important challenge to what was later known as Keynesian macroeconomics. Today, economists are once again paying heed to Hayek's thoughts. This volume bring together his work on what causes periods of boom and bust in the economy.

This text addresses the profound human questions of love and work. Beginning with a historical introduction, the author progresses through adaptive problems that humans face, and concludes by showing how evolutionary psychology encompasses all branches of psychology.

Contemporary mate preferences can provide important clues to human reproductive history. Little is known about which characteristics people value in potential mates. Five predictions were made about sex differences in human mate preferences based on evolutionary conceptions of parental investment, sexual selection, human reproductive capacity, and sexual asymmetries regarding certainty of paternity versus maternity. The predictions centered on how each sex valued earning capacity, ambition— industriousness, youth, physical attractiveness, and chastity. Predictions were tested in data from 37 samples drawn from (...) 33 countries located on six continents and five islands. For 27 countries, demographic data on actual age at marriage provided a validity check on questionnaire data. Females were found to value cues toresource acquisitionin potential mates more highly than males. Characteristics signalingreproductive capacitywere valued more by males than by females. These sex differences may reflect different evolutionary selection pressures on human males and females; they provide powerful cross-cultural evidence of current sex differences in reproductive strategies. Discussion focuses on proximate mechanisms underlying mate preferences, consequences for human intrasexual competition, and the limitations of this study. (shrink)

To be autonomous is to be a law to oneself; autonomous agents are self-governing agents. Most of us want to be autonomous because we want to be accountable for what we do, and because it seems that if we are not the ones calling the shots, then we cannot be accountable. More importantly, perhaps, the value of autonomy is tied to the value of self-integration. We don't want to be alien to, or at war with, ourselves; and it seems that (...) when our intentions are not under our own control, we suffer from self-alienation. What conditions must be satisfied in order to ensure that we govern ourselves when we act? Philosophers have offered a wide range of competing answers to this question. (shrink)

Buss, S.R., The undecidability of k-provability, Annals of Pure and Applied Logic 53 75-102. The k-provability problem is, given a first-order formula ø and an integer k, to determine if ø has a proof consisting of k or fewer lines . This paper shows that the k-provability problem for the sequent calculus is undecidable. Indeed, for every r.e. set X there is a formula ø and an integer k such that for all n,ø has a proof of k sequents (...) if and only if n ε X. (shrink)

This volume contains articles covering a broad spectrum of proof theory, with an emphasis on its mathematical aspects. The articles should not only be interesting to specialists of proof theory, but should also be accessible to a diverse audience, including logicians, mathematicians, computer scientists and philosophers. Many of the central topics of proof theory have been included in a self-contained expository of articles, covered in great detail and depth. The chapters are arranged so that the two introductory articles come first; (...) these are then followed by articles from core classical areas of proof theory; the handbook concludes with articles that deal with topics closely related to computer science. (shrink)

In order to be a self-governing agent, a person must govern the process by means of which she acquires the intention to act as she does. But what does governing this process require? The standard compatibilist answers to this question all assume that autonomous actions differ from nonautonomous actions insofar as they are a more perfect expression of the agent’s agency. I challenge this conception of autonomous agents as super agents. The distinguishing feature of autonomous agents is, I argue, the (...) nonagential role they play in the formation of their intentions. I offer an account of the relevant role. (shrink)

We believe we owe one another respect. We believe we ought to pay what we owe by treating one another ‘with respect.’ If we could understand these beliefs we would be well on the way to understanding morality itself. If we could justify these beliefs we could vindicate a central part of our moral experience.Respect comes in many varieties. We respect some people for their upright character, others for their exceptional achievements. There are people we respect as forces of nature: (...) we go to great lengths to accommodate their moods, wiles, and demands. Finally, most of us seem to respect people simply because they are people. This is the sort of respect of special interest to moral theory.In order to be worthy of this last sort of respect, it is not only sufficient but necessary that one be a person. We can, of course, take a similar attitude towardnonpersons. (shrink)

The original essays in this book address Harry Frankfurt's influential writing on personal identity, love, value, moral responsibility, and the freedom and ...

Samuel R. Buss and Aleksandar Ignjatović. Unprovability of Consistency Statements in Fragments of Bounded Arithmetic.

Cook and Reckhow defined a propositional formulation of the pigeonhole principle. This paper shows that there are Frege proofs of this propositional pigeonhole principle of polynomial size. This together with a result of Haken gives another proof of Urquhart's theorem that Frege systems have an exponential speedup over resolution. We also discuss connections to provability in theories of bounded arithmetic.

Partial consistency statements can be expressed as polynomial-size propositional formulas. Frege proof systems have polynomial-size partial self-consistency proofs. Frege proof systems have polynomial-size proofs of partial consistency of extended Frege proof systems if and only if Frege proof systems polynomially simulate extended Frege proof systems. We give a new proof of Reckhow's theorem that any two Frege proof systems p-simulate each other. The proofs depend on polynomial size propositional formulas defining the truth of propositional formulas. These are already known to (...) exist since the Boolean formula value problem is in alternating logarithmic time; this paper presents a proof of this fact based on a construction which is somewhat simpler than the prior proofs of Buss and of Buss-Cook- Gupta-Ramachandran. (shrink)

I wish more books of philosophy were like this one. It is elegantly written. It is filled with provocative claims and ingenious arguments. It is a really good read, even while it forces us to rethink many of our assumptions about practical reason and practical reasoning, morality and agency.

My chief aim is to explain how someone can act freely against her own best judgment. But I also have a second aim: to defend a conception of practical rationality according to which someone cannot do something freely if she believes it would be better to do something else. These aims may appear incompatible. But I argue that practical reason has the capacity to undermine itself in such a way that it produces reasons for behaving irrationally. Weakness of will is (...) possible because it is possible to conclude that one has sufficient reason to reject the verdicts of one's own reason. (shrink)

Let T be a first-order theory. A T-normal Kripke structure is one in which every world is a classical model of T. This paper gives a characterization of the intuitionistic theory T of sentences intuitionistically valid in all T-normal Kripke structures and proves the corresponding soundness and completeness theorems. For Peano arithmetic , the theory PA is a proper subtheory of Heyting arithmetic , so HA is complete but not sound for PA-normal Kripke structures.

The bounded arithmetic theory S2 is finitely axiomatized if and only if the polynomial hierarchy provably collapses. If T2i equals S2i + 1 then T2i is equal to S2 and proves that the polynomial time hierarchy collapses to ∑i + 3p, and, in fact, to the Boolean hierarchy over ∑i + 2p and to ∑i + 1p/poly.

This paper discusses lower bounds for proof length, especially as measured by number of steps (inferences). We give the first publicly known proof of Gödel's claim that there is superrecursive (in fact. unbounded) proof speedup of (i + 1)st-order arithmetic over ith-order arithmetic, where arithmetic is formalized in Hilbert-style calculi with + and · as function symbols or with the language of PRA. The same results are established for any weakly schematic formalization of higher-order logic: this allows all tautologies as (...) axioms and allows all generalizations of axioms as axioms. Our first proof of Gödel's claim is based on self-referential sentences: we give a second proof that avoids the use of self-reference based loosely on a method of Statman. (shrink)

One of the most significant shifts in current thinking on war and gender is the recognition that rape in wartime is not a simple by-product of war, but often a planned and targeted policy. For many feminists ‘rape as a weapon of war’ provides a way to articulate the systematic, pervasive, and orchestrated nature of wartime sexual violence that marks it as integral rather than incidental to war. This recognition of rape as a weapon of war has taken on legal (...) significance at the Rwandan and Yugoslav Tribunals where rape has been prosecuted as a crime against humanity and genocide. In this paper, I examine how the Rwanda Tribunal’s record of judgments conceives of rape enacted as an instrument of the genocide. I consider in particular how the Tribunal’s conception of ‘rape as a weapon of war’ shapes what can be known about sexual violence and gender in the Rwandan genocide and what cannot, the categories of victims legally recognised and those that are not, and the questions pursued, and those foreclosed, about the patterns of violence before and during the genocide. (shrink)

Inductive Metaphysics combines an anti-aprioristic emphasis on an empirical and scientific basis for metaphysics with an insistence on a specifically philosophical abductive theory-building. Since the latter specifically philosophical work is not empirical itself, it may in a liberal sense be called apriori. This paper highlights this apriori dimension within IM by a case study on Structuralism, the view that fundamental reality consists of a network of relations, which a number of philosophers consider to be suggested by modern physics. Focussing on (...) Dasgupta’s algebraic Generalism, the author argues that Structuralism suffers from a severe entailment problem, because the relations-spanning apparatus must stand for metaphysically fundamental forms. Schaffer’s contention that there are no entailment problems is rejected. Advocates of IM are well advised to take seriously their own insistence on metaphysical abduction and not to one-sidedly emphasise the empirical input: the elaboration of exact metaphysical theories and the apriori evaluation of their inherent tenability is a constituent of IM no less important than the consideration of scientific input. More traditional ways of metaphysical reasoning inevitably survive as an essential dimension within IM. (shrink)

The four authors present their speculations about the future developments of mathematical logic in the twenty-first century. The areas of recursion theory, proof theory and logic for computer science, model theory, and set theory are discussed independently.

Strong dispositional monism, the position that all fundamental physical properties consist in dispositional relations to other properties, is naturally construed as property structuralism. J. Lowe’s circularity/regress objection constitutes a serious challenge to SDM that questions the possibility of a purely relational determination of all property essences. The supervenience thesis of A. Bird’s graph-theoretic asymmetry reply to CRO can be rigorously proved. Yet the reply fails metaphysically, because it reveals neither a metaphysical determination of identities on a purely relational basis nor (...) a determination specifically of identities in the sense of essences. Asymmetry is thus not by itself sufficient for a solution to CRO. But it cannot even help to answer CRO when a model for the determination of essences is taken as a basis. Nor is asymmetry necessary for a reply, as property structures may well be symmetric. A metaphysics of dispositional properties as grounded in a purely relational structure faces serious obstacles, and the properties would not be fundamental. Since essence and grounding are notions of metaphysical priority, there can be no essentially dispositional metaphysically fundamental properties, and the prospects of a “coherentist” metaphysics of basic properties are dim. A modal retreat that refrains from a post-modal conception of essence and simply claims that fundamental properties play dispositional roles by metaphysical necessity is unsatisfactory. (shrink)

Resemblance Nominalism About Perfect Naturalness is the view that perfect naturalness of classes is best defined by a conceptual primitive of resemblance between particulars. The adequacy of RNPN is defended by outlining nominalism as the strictly anti-constitutive view that the particulars’ being the fundamental ways they are is not constituted by anything further, supplying a doubly plural contrastive and graded resemblance predicate that allows for a definition of perfect naturalness on an actualist basis, and proving a representation and a uniqueness (...) theorem on the basis of a formal constraint on resemblance called “the Principle”, thereby revealing that bodies of nominalist resemblance facts are guaranteed to behave as if they were grounded in patterns of universals distributed over particulars. (shrink)

We study the long-standing open problem of giving$\forall {\rm{\Sigma }}_1^b$separations for fragments of bounded arithmetic in the relativized setting. Rather than considering the usual fragments defined by the amount of induction they allow, we study Jeřábek’s theories for approximate counting and their subtheories. We show that the$\forall {\rm{\Sigma }}_1^b$Herbrandized ordering principle is unprovable in a fragment of bounded arithmetic that includes the injective weak pigeonhole principle for polynomial time functions, and also in a fragment that includes the surjective weak pigeonhole (...) principle for FPNPfunctions. We further give new propositional translations, in terms of random resolution refutations, for the consequences of$T_2^1$augmented with the surjective weak pigeonhole principle for polynomial time functions. (shrink)

The paper proves refined feasibility properties for the disjunction property of intuitionistic propositional logic. We prove that it is possible to eliminate all cuts from an intuitionistic proof, propositional or first-order, without increasing the Horn closure of the proof. We obtain a polynomial time, interactive, realizability algorithm for propositional intuitionistic proofs. The feasibility of the disjunction property is proved for sequents containing Harrop formulas. Under hardness assumptions for NP and for factoring, it is shown that the intuitionistic propositional calculus does (...) not always have polynomial size proofs and that the classical propositional calculus provides a superpolynomial speedup over the intuitionistic propositional calculus. The disjunction property for intuitionistic propositional logic is proved to be P-hard by a reduction to the circuit value problem. (shrink)

This paper considers the computational complexity of the disjunction and existential properties of intuitionistic logic. We prove that the disjunction property holds feasibly for intuitionistic propositional logic; i.e., from a proof of A v B, a proof either of A or of B can be found in polynomial time. For intuitionistic predicate logic, we prove superexponential lower bounds for the disjunction property, namely, there is a superexponential lower bound on the time required, given a proof of A v B, to (...) produce one of A and B which is true. In addition, there is superexponential lower bound on the size of terms which fulfill the existential property of intuitionistic predicate logic. There are superexponential upper bounds for these problems, so the lower bounds are essentially optimal. (shrink)

C'est sur la nécessité de l'absence d'une telle définition que Julien Busse invite à se pencher pour en analyser aussi bien les causes que les effets.

Modern evolutionary psychology provides a cogent criterion for considering an emotion as “basic”: Whether the emotion evolved to solve an adaptive problem tributary to reproduction. Criteria such as distinctive universal signals, presence in other primates, or contribution to survival are not relevant, even though some basic emotions have these properties. Abundant evidence suggests that sexual jealousy is properly considered a basic emotion, even though it lacks a distinct expressive signature, contributes to adaptive problems of mating rather than survival, and may (...) or may not be present in other primates. (shrink)

The paper offers insights into the acceptability of ethical issues in poultry production and how this situation provides an opportunity to transform the prevailing system into a more sustainable one. The survey among German consumers reveals that killing day-old chicks is a well-known practice and is rated as “very problematic”. In contrast, dual-purpose chickens are mostly unknown but are considered a positive alternative to killing day-old chicks. Consumer clusters were identified regarding purchasing criteria for dual-purpose chickens, purchasing routines and socio-economic (...) factors. Three of the five clusters—the perfectionists, idealists, and realists—turned out to be potential buyers. To develop a suitable marketing strategy, it is recommended that the added value of dual-purpose chickens be comprehensibly communicated. From a multi-level perspective, rearing dual-purpose chickens has a competitive disadvantage compared to system-compliant alternatives. Through increasing external pressure, the different alternatives can jointly contribute to a regime shift. (shrink)

Contemporary mate preferences can provide important clues to human reproductive history. Little is known about which characteristics people value in potential mates. Five predictions were made about sex differences in human mate preferences based on evolutionary conceptions of parental investment, sexual selection, human reproductive capacity, and sexual asymmetries regarding certainty of paternity versus maternity. The predictions centered on how each sex valued earning capacity, ambition— industriousness, youth, physical attractiveness, and chastity. Predictions were tested in data from 37 samples drawn from (...) 33 countries located on six continents and five islands. For 27 countries, demographic data on actual age at marriage provided a validity check on questionnaire data. Females were found to value cues toresource acquisitionin potential mates more highly than males. Characteristics signalingreproductive capacitywere valued more by males than by females. These sex differences may reflect different evolutionary selection pressures on human males and females; they provide powerful cross-cultural evidence of current sex differences in reproductive strategies. Discussion focuses on proximate mechanisms underlying mate preferences, consequences for human intrasexual competition, and the limitations of this study. (shrink)

In the context of a largely exploratory inquiry, I warn against oversimplifying the relationships among intuitions, emotions, principle-governed reasoning, and responsiveness to reasons. I point out that one cannot determine the normative status of some fact without determining whether a case can be made for this status. But I also note that, though reason is thus autonomous, every episode of reasoning depends causally on the way things nonnormatively are, and this makes it possible for any reasoner to challenge even her (...) most basic normative assumptions. (shrink)

We give a uniform proof of the theorems of Yao and Beigel–Tarui representing ACC predicates as constant depth circuits with MODm\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\hbox {MOD}_{m}$$\end{document} gates and a symmetric gate. The proof is based on a relativized, generalized form of Toda’s theorem expressed in terms of closure properties of formulas under bounded universal, existential and modular counting quantifiers. This allows the main proofs to be expressed in terms of formula classes instead of Boolean circuits. (...) The uniform version of the Beigel–Tarui theorem is then obtained automatically via the Furst–Saxe–Sipser and Paris–Wilkie translations. As a special case, we obtain a uniform version of Razborov and Smolensky’s representation of AC0[p]\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\hbox {AC}^{0}[p]$$\end{document} circuits. The paper is partly expository, but is also motivated by the desire to recast Toda’s theorem, the Beigel–Tarui theorem, and their proofs into the language of bounded arithmetic. However, no knowledge of bounded arithmetic is needed. (shrink)