Comprehensive account of constructive theory of first-order predicate calculus. Covers formal methods including algorithms and epi-theory, brief treatment of Markov’s approach to algorithms, elementary facts about lattices and similar algebraic systems, more. Philosophical and reflective as well as mathematical. Graduate-level course. 1963 ed. Exercises.

The Peanese convention for the use of dots as brackets has the disadvantage that it gives only an awkward method for representing chains of indefinite length, such as the compound implicationSuch chains occur frequently in logical investigations of a metatheoretic nature, and it is convenient to have a systematic method of abbreviating them. The most obvious method of doing this would be to leave the parentheses out entirely, and to understand that in such cases the implication sign or other operation (...) appearing on the extreme left is the most inclusive; but this method, which has been followed by Quine, is at variance with our ordinary algebraic usage, in which we write a − b + c − d for ((a − b) + c) − d, and consequently leads to confusion. It is desirable to have a modification of the Peanese convention which gives a simple method of representing such chain implications, and at the same time avoids this difficulty.Such a modification is easily obtained by generalizing somewhat a procedure of Church. The latter author uses only a single dot, which he writes on the right of an operator to signify a bracket extending from that point to the end of the formula (or parenthesized expression). If dots are used only on the right of operations this is all that can be desired. But the essential idea of this device can be extended to the case where dots are used also on the left, as follows: let us suppose that a group of dots on the right of an operation or prefix denotes the beginning of a bracket which extends to the right until it meets a group with an equal or larger number of dots on the left of an operation; and that the scope of a group of dots on the left of an operation shall extend to the left until it reaches a larger group of dots on the right of some operation. (shrink)

We expose some basic elements of a style of programming supported by functional languages like Haskell by relating them to a coherent set of notions and techniques from Curry’s work in combinatory logic and formal systems, and their algebraic and categorical interpretations. Our account takes the form of a commentary to a simple fragment of Haskell code attempting to isolate the conceptual sources of the linguistic abstractions involved.

The relation between least and diagonal fixed points is a well known and completely studied question for a large class of partially ordered models of the lambda calculus and combinatory logic. Here we consider this question in the context of algebraic recursion theory, whose close connection with combinatory logic recently become apparent. We find a comparatively simple and rather weak general condition which suffices to prove the equality of least fixed points with canonical (corresponding to those produced by the (...) class='Hi'>Curry combinator in lambda calculus) diagonal fixed points in a class of partially ordered algebras which covers both combinatory spaces of Skordev and operative spaces of Ivanov. Especially, this yields an essential improvement of the axiomatization of recursion theory via combinatory spaces. (shrink)

This important book provides a theory about the nature of fiction, and about the relation between the author, the reader and the fictional text. The approach is philosophical: that is to say, the author offers an account of key concepts such as fictional truth, fictional characters, and fiction itself. The book argues that the concept of fiction can be explained partly in terms of communicative intentions, partly in terms of a condition which excludes relations of counterfactual dependence between the world (...) and the text. This communicative model is then applied to the following problems: how can something be 'true in the story' without being explicitly stated in the text? In what ways does interpreting a fictional story depend upon grasping its author's intentions? Is there always a unique best interpretation of a fictional text? What is the correct semantics for fictional names? What is the nature of our emotional response to a fictional work? In answering these questions the author explores the complex interaction between author, reader, and text. This interaction requires the reader to construct a 'fictional author' - a character in the story whose personality, beliefs and emotional states must be interpreted if the reader is to grasp the meaning of the work. (shrink)

El objetivo de este artículo es discutir la concepción cartesiana del Álgebra como una lógica del descubrimiento científico. En la introducción al artículo discutimos algunas de las interpretaciones más conocidas sobre el valor de la Matemática cartesiana. En la primera parte de este trabajo, realizamos una contraposición entre los pensamientos de Aristóteles y de Descartes sobre las teorías deductivas. En la segunda parte, analizamos las consideraciones hechas por Descartes sobre el valor de la Lógica. En latercera parte, nos ocupamos específicamente (...) con la concepción cartesiana del Álgebra.The goal of the present paper is to discuss some of the aspects of Descartes’ thoughts on Algebra. The Introduction is dedicated to discussing some ofthe interpretations of Cartesian mathematics. In the first part of this article,Cartesians and Aristotelians views on deductive theories are opposed. In the second part the Cartesian criticism of Aristotelian Logic is analyzed. In the third part the Cartesian concept of Algebra as a Logic of discovery is evaluated. (shrink)

We describe a class of MV-algebras which is a natural generalization of the class of “algebras of continuous functions”. More specifically, we're interested in the algebra of frame maps Hom\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${_{\cal F}}$$\end{document} (Ω(A), K) in the category T of frames, where A is a topological MV-algebra, Ω(A) the lattice of open sets of A, and K an arbitrary frame.Given a topological space X and a topological MV-algebra A, we have the (...) algebra C (X, A) of continuous functions from X to A. We can look at this from a frame point of view. Among others we have the result: if K is spatial, then C(pt(K), A), pt(K) the points of K, embeds into Hom\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${_{\cal F}}$$\end{document} (Ω(A), K) analogous to the case of C (X, A) embedding into Hom\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${_{\cal F}}$$\end{document} (Ω(A), Ω (X)). (shrink)

O caráter protocolar desempenhado pelas matemáticas na formulação do conceito cartesiano de ciência é amplamente difundido e frequentemente reinvocado na literatura especializada quando se trata de abordar a exigência apodítica inerente a este conceito. No entanto, pouco se explora o que a diversidade das disciplinas matemáticas bem como a relação entretida por elas permite trazer de elucidação à noção cartesiana de ciência. Nosso propósito consiste, aqui, em tomar posição quanto a um debate acerca do estatuto da álgebra e da geometria (...) como disciplinas que fixam os lineamentos da teoria cartesiana do conhecimento ao exibirem o que Descartes reputaria como a aplicação ideal do intelecto. Trata-se de insistir, por vias que assinalam uma decisão teórica em favor de uma concepção mais intelectualista e menos imaginativa da ciência, que não há hesitação quanto ao papel primitivo e fundacional da álgebra se comparada à geometria. (shrink)

In this essay I will defend three points, the first being that Descartes- unlike the aristotelian traditon- maintained that abstraction is not a operation in which the intellect builds the mathematical object resorting to sensible ob- jects. Secondly I will demonstrate that, according to cartesian philosophy, the faculty of understanding has the ability to instatiate- within the process of abstraction- mathematical symbols that represent the relation between quantities, whether magnitude or multitude.And finally I will advocate that the lack of onthological (...) commitment with sensible experience found in cartesian philosophy of mathematics allows for the creation of a mathematical language that regards the objects of geometry and arithmetics through a system of rules and notations, in other words, algebra. (shrink)

This paper is an attempt to clear some philosophical questions about the nature of logic by setting up a mathematical framework. The notion of congruence in logic is defined. A logical structure in which there is no non-trivial congruence relation, like some paraconsistent logics, is called simple. The relations between simplicity, the replacement theorem and algebraization of logic are studied (including MacLane-Curry’s theorem and a discussion about Curry’s algebras). We also examine how these concepts are related to (...) such notions as semantics, truth-functionality and bivalence. We argue that a logic, which is simple, can deserve the name logic and that the opposite view is connected with a reductionist perspective (reduction of logic to algebra). (shrink)

An argument that we should be optimistic about the capacity of “methodologically omnivorous” geologists, paleontologists, and archaeologists to uncover truths about the deep past. -/- The “historical sciences”—geology, paleontology, and archaeology—have made extraordinary progress in advancing our understanding of the deep past. How has this been possible, given that the evidence they have to work with offers mere traces of the past? In Rock, Bone, and Ruin, Adrian Currie explains that these scientists are “methodological omnivores,” with a variety of strategies (...) and techniques at their disposal, and that this gives us every reason to be optimistic about their capacity to uncover truths about prehistory. Creative and opportunistic paleontologists, for example, discovered and described a new species of prehistoric duck-billed platypus from a single fossilized tooth. Examining the complex reasoning processes of historical science, Currie also considers philosophical and scientific reflection on the relationship between past and present, the nature of evidence, contingency, and scientific progress. -/- Currie draws on varied examples from across the historical sciences, from Mayan ritual sacrifice to giant Mesozoic fleas to Mars's mysterious watery past, to develop an account of the nature of, and resources available to, historical science. He presents two major case studies: the emerging explanation of sauropod size, and the “snowball earth” hypothesis that accounts for signs of glaciation in Neoproterozoic tropics. He develops the Ripple Model of Evidence to analyze “unlucky circumstances” in scientific investigation; examines and refutes arguments for pessimism about the capacity of the historical sciences, defending the role of analogy and arguing that simulations have an experiment-like function. Currie argues for a creative, open-ended approach, “empirically grounded” speculation. (shrink)

We describe a class of MV-algebras which is a natural generalization of the class of "algebras of continuous functions". More specifically, we're interested in the algebra of frame maps $Hom_{\scr{F}}(\Omega (A),\text{K})$ in the category $\scr{F}$ of frames, where A is a topological MV-algebra, Ω(A) the lattice of open sets of A, and K an arbitrary frame. Given a topological space X and a topological MV-algebra A, we have the algebra C(X, A) of continuous functions from X to A. (...) We can look at this from a frame point of view. Among others we have the result: if K is spatial, then C(pt(K), A), pt(K) the points of K, embeds into $Hom_{\scr{F}}(\Omega (A),\text{K})$ analogous to the case of C(X, A) embedding into $Hom_{\scr{F}}(\Omega (A),\Omega (X))$. (shrink)

This chapter is a manifesto of the film theory of Gregory Currie. He thinks that his work brings a connection between film and cognitive psychology. The chapter begins with a glimpse of an ideal theoretical structure and his opinion on the philosophical background against the manifesto itself. Then the theses and the arguments on film theory and the philosophy of film, moving pictures, convention, intention, and genre, and the viewer is laid out. The description includes an outline of what he (...) thinks is the ideal abstract structure for the film theory. He hoped that by doing this, he would contribute to the exemplification of the structure. The manifesto aims to promote the following: open criticism from the outside, struggle for inner coherence, comprehensiveness, and intuitive judgment. It is evident that his work is in a top-down mode which is why it is called a nervous manifesto. (shrink)

Imre Lakatos' philosophical and scientific papers are published here in two volumes. Volume I brings together his very influential but scattered papers on the philosophy of the physical sciences, and includes one important unpublished essay on the effect of Newton's scientific achievement. Volume 2 presents his work on the philosophy of mathematics (much of it unpublished), together with some critical essays on contemporary philosophers of science and some famous polemical writings on political and educational issues.

I shall argue that cinematic images do not have tense: not, at least, in the sense that has been ascribed to them by film theorists. This does not abolish time in cinema, for there can be temporal relations without tense, and temporal relations between cinematic images can indicate temporal relations between events depicted. But the dispensability of tense will require us to rethink our assumptions about what is sometimes called anachrony in cinema: the reordering of story-time by narrative, of which (...) the flashback is the most common example. (shrink)

Recreative Minds develops a philosophical theory of imagination that draws upon the latest work in psychology. This theory illuminates the use of imagination in coming to terms with art, its role in enabling us to live as social beings, and the psychological consequences of disordered imagination. The authors offer a lucid exploration of a fascinating subject.

Sparsity, Structure, Scaling and Stability in Computational Linear Algebra. Tutorial book for the IX Brazilian Computer Science School, held at Recife, in 1994.

Many biological investigations are organized around a small group of species, often referred to as ‘model organisms’, such as the fruit fly Drosophila melanogaster. The terms ‘model’ and ‘modelling’ also occur in biology in association with mathematical and mechanistic theorizing, as in the Lotka–Volterra model of predator-prey dynamics. What is the relation between theoretical models and model organisms? Are these models in the same sense? We offer an account on which the two practices are shown to have different epistemic characters. (...) Theoretical modelling is grounded in explicit and known analogies between model and target. By contrast, inferences from model organisms are empirical extrapolations. Often such extrapolation is based on shared ancestry, sometimes in conjunction with other empirical information. One implication is that such inferences are unique to biology, whereas theoretical models are common across many disciplines. We close by discussing the diversity of uses to which model organisms are put, suggesting how these relate to our overall account. 1 Introduction2 Volterra and Theoretical Modelling3 Drosophila as a Model Organism4 Generalizing from Work on Model Organisms5 Phylogenetic Inference and Model Organisms6 Further Roles of Model Organisms6.1 Preparative experimentation6.2 Model organisms as paradigms6.3 Model organisms as theoretical models6.4 Inspiration for engineers6.5 Anchoring a research community7 Conclusion. (shrink)