This is the first comprehensive study of Schrödinger's scientific and philosophical writings. The task requires a person trained thoroughly in physical science and yet capable of appreciating the sometimes puzzling philosophical ideas Schrödinger put forward. Professor Scott, a physicist, is remarkably successful at communicating both the physical and the philosophical ideas. After a brief summary of Schrödinger's diverse writings, he divides the writings into four groups which are treated in separate chapters. The first group, including very early papers, deals with (...) Schrödinger's work on Statistical Mechanics, and statistical theories in general. The second covers the crucial development of Wave Mechanics. The third concerns Schrödinger's interpretation of quantum mechanics and the important departures from the prevailing views of the Copenhagen school. Finally the fourth group contains Schrödinger's views on life and the self. The author shows that Schrödinger was led to his doctrine of identity by reflecting on the paradox of freedom and determinism. His study "What is Life?" convinced him that living systems are governed by the law of causality but he also believed that men were free. The doctrine of identity was his solution to the paradox. Scott is critical of this solution and a number of other doctrines of Schrödinger. The book is clearly written throughout and is a good introduction to Schrödinger's thought.--R. H. K. (shrink)

This is the first comprehensive study of Schrödinger's scientific and philosophical writings. The task requires a person trained thoroughly in physical science and yet capable of appreciating the sometimes puzzling philosophical ideas Schrödinger put forward. Professor Scott, a physicist, is remarkably successful at communicating both the physical and the philosophical ideas. After a brief summary of Schrödinger's diverse writings, he divides the writings into four groups which are treated in separate chapters. The first group, including very early papers, deals with (...) Schrödinger's work on Statistical Mechanics, and statistical theories in general. The second covers the crucial development of Wave Mechanics. The third concerns Schrödinger's interpretation of quantum mechanics and the important departures from the prevailing views of the Copenhagen school. Finally the fourth group contains Schrödinger's views on life and the self. The author shows that Schrödinger was led to his doctrine of identity by reflecting on the paradox of freedom and determinism. His study "What is Life?" convinced him that living systems are governed by the law of causality but he also believed that men were free. The doctrine of identity was his solution to the paradox. Scott is critical of this solution and a number of other doctrines of Schrödinger. The book is clearly written throughout and is a good introduction to Schrödinger's thought.--R. H. K. (shrink)

The distribution of organisms in morphologic space is clumpy. Cats are like felids, dogs are like canids and snails are (mostly) like gastropods. But cats are not like dogs and snails are not like clams. This clumpy distribution of morphology has long posed one of the greatest challenges to evolutionary biologists. Does it represent the extinction and disappearance of a oncecontinuous distribution of morphologies, clades perched on the summits of persistent selective peaks ala Sewell Wright, or a primary signature of (...) the evolutionary processes? And if the latter, what processes are responsible for generating it? Although often couched in discussions of the origin of higher taxa, such taxa are but proxies for this clumpy distribution, and ultimately the latter is the critical issue for macroevolution and for Stephen Jay Gould’s opus. Underneath all the controversies over whether species constitute individuals, whether speciation serves to divide intra-specific adaptation driven by natural selection from a set of inter- and supra-specific evolutionary processes, and over the impact of catastrophic mass extinctions on evolutionary trends, the fundamental issue is simply one of clumpiness (or, if you prefer, the inhomogeneous distribution of morphologies). Iurii Filipchenko, a Russian geneticist and the mentor of Theodosius Dobzhansky, introduced the term macroevolution in 1927 because he believed that the origin of the characters associated with higher taxa (those beyond the species level) required a different process of evolution. Filipchenko believed macroevolution was driven by cytoplasmic inheritance, but his general argument was consistent with other saltationists and macro-mutationists of the time, including the paleontologist Henry Fairfield Osborne and the geneticist Richard Goldschmidt. These evolutionary biologists shared the.. (shrink)

Eric Davidson had a deep and abiding interest in the role developmental mechanisms played in generating evolutionary patterns documented in deep time, from the origin of the euechinoids to the processes responsible for the morphological architectures of major animal clades. Although not an evolutionary biologist, Davidson’s interests long preceded the current excitement over comparative evolutionary developmental biology. Here I discuss three aspects at the intersection between his research and evolutionary patterns in deep time: First, understanding the mechanisms of body plan (...) formation, particularly those associated with the early diversification of major metazoan clades. Second, a critique of early claims about ancestral metazoans based on the discoveries of highly conserved genes across bilaterian animals. Third, Davidson’s own involvement in paleontology through a collaborative study of the fossil embryos from the Ediacaran Doushantuo Formation in south China. (shrink)

Have the large-scale evolutionary patterns illustrated by the fossil record been driven by fluctuations in environmental opportunity, by biotic factors, or by changes in the types of phenotypic variants available for evolutionary change? Since the Modern Synthesis most evolutionary biologists have maintained that microevolutionary processes carrying on over sufficient time will generate macroevolutionary patterns, with no need for other pattern-generating mechanisms such as punctuated equilibrium or species selection. This view was challenged by paleontologists in the 1970s with proposals that the (...) differential sorting and selection of species and clades, and the effects of biotic crises such as mass extinctions, were important extensions to traditional evolutionary theory. More recently those interested in macroevolution have debated the relative importance of abiotic and biotic factors in driving macroevolutionary patterns and have introduced comparative phylogenetic methods to analyze the rates of change in taxonomic diversity. Applying Peter Godfrey-Smith’s distinction between distributional explanations and explanations focusing on the origin of variation, most macroevolutionary studies have provided distributional explanations of macroevolutionary patterns. Comparative studies of developmental evolution, however, have implicated the origin of variants as a driving macroevolution force. In particular, the repatterning of gene regulatory networks provides new insights into the origins of developmental novelties. This raises the question of whether macroevolution has been pulled by the generation of environmental opportunity, or pushed by the introduction of new morphologies. The contrast between distributional and origination scenarios has implications for understanding evolutionary novelty and innovation and how macroevolutionary process may have evolved over time. (shrink)

Combinatory logic started as a programme in the foundation of mathematics and in an historical context at a time when such endeavours attracted the most gifted among the mathematicians. This small volume arose under quite differ ent circumstances, namely within the context of reworking the mathematical foundations of computer science. I have been very lucky in finding gifted students who agreed to work with me and chose, for their Ph. D. theses, subjects that arose from my own attempts 1 to (...) create a coherent mathematical view of these foundations. The result of this collaborative work is presented here in the hope that it does justice to the individual contributor and that the reader has a chance of judging the work as a whole. E. Engeler ETH Zurich, April 1994 lCollected in Chapter III, An Algebraization of Algorithmics, in Algorithmic Properties of Structures, Selected Papers of Erwin Engeler, World Scientific PubJ. Co. , Singapore, 1993, pp. 183-257. I Historical and Philosophical Background Erwin Engeler In the fall of 1928 a young American turned up at the Mathematical Institute of Gottingen, a mecca of mathematicians at the time; he was a young man with a dream and his name was H. B. Curry. He felt that he had the tools in hand with which to solve the problem of foundations of mathematics mice and for all. His was an approach that came to be called "formalist" and embodied that later became known as Combinatory Logic. (shrink)