Formal Mathematical Systems Research Articles

On the Origins of Randomness

AbstractThis paper is a concept paper, which discusses the definition of randomness, and the sources of randomness in the physical system (the Universe) as well as in the formal mathematical system. I discuss how randomness, through chaos, the second law, the quantum mechanical character of small scales, and stochasticity is an intrinsic property of nature. I then move to our formal mathematical system and show that even in this formal system we cannot do away with randomness and that the randomness in the physical world is consistent with the origins of randomness suggested from the study of mathematical systems. Rules and randomness are blended together and their interaction is shaping all observed forms and structures.

The Fall and Original Sin of Set Theory

Hermann Weyl published a brief survey as preface to a review of The Philosophy of Bertrand Russell in 1946. In this survey he used the phrase, “The Fall and Original Sin of Set Theory.” Investigating the background of this remark will require that we pay attention to a number of issues within the foundations of mathematics. For example: Did God make the integers—as Kronecker alleged? Is mathematics set theory? Attention will also be given to axiomatic set theory and relevant ontic pre-conditions, such as the difference between number and number symbols, to number as “an aspect of objective reality” (Gödel), integers and induction (Skolem) as well as to the question if infinity—as endlessness—could be completed. In 1831 Gauss objected to viewing the infinite as something completed, which is not allowed in mathematics. It will be argued that the actual infinite is rather connected to what is present “at once,” as an infinite totality. By the year 1900 mathematicians believed that mathematics had reached absolute rigour, but unfortunately the rest of the twentieth century witnessed the opposite. The axiom of infinity ruined the expectations of logicism—mathematics cannot be reduced to logic. The intuitionism of Brouwer, Weyl and others launched a devastating attack on classical analysis, further inspired by the outcome of Gödel’s famous proof of 1931, in which he has shown that a formal mathematical system is inconsistent or incomplete. Intuitionism created a whole new mathematics, which finds no counter-part in classical mathematics. Slater remarked that within this logical paradise of Russell lurked a serpent, hidden behind the unjustified employment of the at once infinite. According to Weyl, “This is the Fall and original sin of set theory for which it is justly punished by the antinomies.” In conclusion, a few systematic distinctions are introduced.

A Dynamic Causal Model of the Coupling Between Pulse Stimulation and Neural Activity

We present a dynamic causal model that can explain context-dependent changes in neural responses, in the rat barrel cortex, to an electrical whisker stimulation at different frequencies. Neural responses were measured in terms of local field potentials. These were converted into current source density (CSD) data, and the time series of the CSD sink was extracted to provide a time series response train. The model structure consists of three layers (approximating the responses from the brain stem to the thalamus and then the barrel cortex), and the latter two layers contain nonlinearly coupled modules of linear second-order dynamic systems. The interaction of these modules forms a nonlinear regulatory system that determines the temporal structure of the neural response amplitude for the thalamic and cortical layers. The model is based on the measured population dynamics of neurons rather than the dynamics of a single neuron and was evaluated against CSD data from experiments with varying stimulation frequency (1-40 Hz), random pulse trains, and awake and anesthetized animals. The model parameters obtained by optimization for different physiological conditions (anesthetized or awake) were significantly different. Following Friston, Mechelli, Turner, and Price (2000), this work is part of a formal mathematical system currently being developed (Zheng et al., 2005) that links stimulation to the blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) signal through neural activity and hemodynamic variables. The importance of the model described here is that it can be used to invert the hemodynamic measurements of changes in blood flow to estimate the underlying neural activity.

Intuition and surprise

PurposeThis editorial seeks to address the importance of intuition and metaphor in the construction of logical systems of thought.Design/methodology/approachTwo unconventional approaches to probability theory are considered, one based upon the non‐intuitive law of the excluded middle, and one based upon the notion of surprise.FindingsIt is argued that formal systems based upon non‐intuitive assumptions/axioms are generally less likely to be accepted by researchers. Nevertheless, it sometimes is possible to identify unconventional systems with greater intuitive appeal than their more orthodox counterparts.Originality/valueThe editorial emphasizes an aspect of formal mathematical systems – intuition – that is often overlooked.

The Intentionality of Formal Systems

One of the most interesting and entertaining philosophical discussions of the last few decades is the discussion between Daniel Dennett and John Searle on the existence of intrinsic intentionality. Dennett denies the existence of phenomena with intrinsic intentionality. Searle, however, is convinced that some mental phenomena exhibit intrinsic intentionality. According to me, this discussion has been obscured by some serious misunderstandings with regard to the concept ‘intrinsic intentionality’. For instance, most philosophers fail to realize that it is possible that the intentionality of a phenomenon is partly intrinsic and partly observer relative. Moreover, many philosophers are mixing up the concepts ‘original intentionality’ and ‘intrinsic intentionality’. In fact, there is, in the philosophical literature, no strict and unambiguous definition of the concept ‘intrinsic intentionality’. In this article, I will try to remedy this. I will also try to give strict and unambiguous definitions of the concepts ‘observer relative intentionality’, ‘original intentionality’, and ‘derived intentionality’. These definitions will be used for an examination of the intentionality of formal mathematical systems. In conclusion, I will make a comparison between the (intrinsic) intentionality of formal mathematical systems on the one hand, and the (intrinsic) intentionality of human beings on the other hand.

The representational theory of measurement: An assessment.

This article assesses the representational theory of measurement, found in mathematical psychology, which construes measurement as the representation of an empirical relational system by a formal mathematical system. To be measurable, a given empirical system must match the characteristics of a formal system, preferably cast in an axiomatic form. This critique argues that representational theory encounters a number of problems as a theory of measurement in natural science. It offers no special advantages as a methodology for social science measurement and needs to be supplemented by construct-related validation procedures

The representational theory of measurement: An assessment.

This article assesses the representational theory of measurement, found in mathematical psychology, which construes measurement as the representation of an empirical relational system by a formal mathematical system. To be measurable, a given empirical system must match the characteristics of a formal system, preferably cast in an axiomatic form. This critique argues that representational theory encounters a number of problems as a theory of measurement in natural science. It offers no special advantages as a methodology for social science measurement and needs to be supplemented by construct-related validation procedures

A Study of the Applications of Analog Computers

An electronic analog computer is a tool for solving mathematical differential equations. The basis for the use of such a computer in the simulation of many scientific and engineering problems is the possibility of characterizing these situations as formal mathematical systems by using differential equations. In this paper, following a brief description of the computing elements, the applications of analog computers in the study of various linear, nonlinear, and time-varying systems are described with typical illustrative examples from diverse fields of interest. Computer applications in solving partial differential equations are also discussed. Potential capabilities and limitations of this type of computer as an aid in research and analysis are given.

Martin Davis. On formally undecidable propositions of the Principia Mathematica and related systems. I. The undecidable, Basic papers on undecidable propositions, unsolvable problems and computable functions, edited by Martin Davis, Raven Press, Hewlett, New York, 1965, p. 4. - Kurt Gödel. On formally undecidable propositions of Principia Mathematica and related systems I. English translation of 4183 by Elliott Mendelson. The

Martin Davis. On formally undecidable propositions of the Principia Mathematica and related systems. I. The undecidable, Basic papers on undecidable propositions, unsolvable problems and computable functions, edited by Martin Davis, Raven Press, Hewlett, New York, 1965, p. 4. - Kurt Gödel. On formally undecidable propositions of Principia Mathematica and related systems I. English translation of 4183 by Elliott Mendelson. The undecidable, Basic papers on undecidable propositions, unsolvable problems and computable functions, edited by Martin Davis, Raven Press, Hewlett, New York, 1965, pp. 5–38. - Martin Davis. On undecidable propositions of formal mathematical systems. The undecidable, Basic papers on undecidable propositions, unsolvable problems and computable functions, edited by Martin Davis, Raven Press, Hewlett, New York, 1965, pp. 39–40. - Kurt Gödel. On undecidable propositions of formal mathematical systems. A revised reprint of 41814. The undecidable, Basic papers on undecidable propositions, unsolvable problems and computable functions, edited by Martin Davis, Raven Press, Hewlett, New York, 1965, pp. 41–71. (See corrigenda, p. 74.) - Kurt Gödel. Postscriptum. The undecidable, Basic papers on undecidable propositions, unsolvable problems and computable functions, edited by Martin Davis, Raven Press, Hewlett, New York, 1965, pp. 71–73. - Kurt Gödel. On intuitionistic arithmetic and number theory. English translation of 41811 by Martin Davis. The undecidable, Basic papers on undecidable propositions, unsolvable problems and computable functions, edited by Martin Davis, Raven Press, Hewlett, New York, 1965, pp. 75–81. - Kurt Gödel. On the length of proofs. English translation of I 116 by Martin Davis. The undecidable, Basic papers on undecidable propositions, unsolvable problems and computable functions, edited by Martin Davis, Raven Press, Hewlett, New York, 1965, pp. 82–83. - Kurt Gödel. Remarks before the Princeton Bicentennial Conference on Problems in Mathematics — 1946. The undecidable, Basic papers on undecidable propositions, unsolvable problems and computable functions, edited by Martin Davis, Raven Press, Hewlett, New York, 1965, pp. 84–88. [Cf. XII 89(2).] - Martin Davis. An unsolvable problem of elementary number theory. The undecidable, Basic papers on undecidable propositions, unsolvable problems and computable functions, edited by Martin Davis, Raven Press, Hewlett, New York, 1965, p. 88. - Alonzo Church. An unsolvable problem of elementary number theory. A reprint of I 73. The undecidable, Basic papers on undecidable propositions, unsolvable problems and computable functions, edited by Martin Davis, Raven Press, Hewlett, New York, 1965, pp. 89–107. - Volume 31 Issue 3

The exclusive disjunction

The study of algebra and geometry as formal mathematical systems introduces various kinds of statements. One of the most basic statements of all is the if-then sentence. Among other ways, statements of mathematics are related to each other by means of this pattern. If-then sentences, in turn, are related to each other to build the structure of mathematics and to formulate proofs.