In this paper I shall venture into an area with which I am not very familiar and in which I feel far from confident; namely into phenomenology. My main motive is not to get away from standard, boring, methodological questions like those of induction and demarcation; but the conviction that a phenomenological account of the empirical basis forms a necessary complement to Popper's falsificationism. According to the latter, a scientific theory is a synthetic and universal, hence unverifiable proposition. In fact, (...) in order to be technologically useful, a scientific hypothesis must refer to future states-of-affairs; it ought therefore to remain unverified. But in order to be empirical, a theory must bear some kind of relation to factual statements. According to Popper, such a relation can only be one of potential conflict. Thus a theory T will be termed scientific if and only if T is logically incompatible with a so-called basic statement b, where b is both empirically verifiable and empirically falsifiable. In other words: T is scientific if it entails ¬b; where b, hence also ¬b, is an empirically decidable proposition. (shrink)

American biologists in the late nineteenth century pioneered the descriptive-comparative study of all cell divisions from zygote to gastrulation -- the cell lineage. Data from cell lineages were crucial to evolutionary and developmental questions of the day. One of the main questions was the ultimate causation of developmental patterns -- historical or mechanical. E. B. Wilson's groundbreaking lineage work on the polychaete worm Nereis in 1892 set the stage for (1) an attack on Haeckel's phylogenetic-historical notion of recapitulation and (2) (...) support for mechanistic explanations of cleavage patterns. As more lineage work -- especially Lillie's work on "Unio" and Conklin's on "Crepidula" -- became available in the mid-late 1890s, mechanism was tempered with more evolutionary, homology-based views. However, as I show by focusing on three major issues -- homology, body plans and life history -- these views were primarily based on the precocious segregation and prospective significance -- what the cell became not what it was. Even on issues like adaptation, most lineagists argued teleologically from the adult backward. Most cell lineage workers, by 1900, were to varying degrees mechanist/experimentalist and recapitulationist simultaneously. The exception was E. G. Conklin, whose views were more akin to a Darwinian evolutionist than either mechanist or recapitulationist. Lineage work eventually declined and by 1907 published accounts of new lineages had basically stopped. I argue that established workers and younger researchers stopped wanting to take on cell lineage projects because the general patterns were the same for all the spiralians while the specifics showed too much variation. It was hard to theoretically encompass or analyze the minutiae of variation in a recapitulationist or mechanist framework. The only established worker who continued to do comparative lineage studies was E. G. Conklin, perhaps because the variation could best be accommodated by Darwinian evolution. (shrink)

The usual way for new cells to come into being is by division of old cells. So the zygote, which is a—new—single cell formed from two, the sperm and ovum, is an exception. Textbooks of human genetics usually say that this new cell is beginning of a new human individual. What this indicates is that they suddenly forget about identical twins.

Originally published in 1965. This is a textbook of modern deductive logic, designed for beginners but leading further into the heart of the subject than most other books of the kind. The fields covered are the Propositional Calculus, the more elementary parts of the Predicate Calculus, and Syllogistic Logic treated from a modern point of view. In each of the systems discussed the main emphases are on Decision Procedures and Axiomatisation, and the material is presented with as much formal rigour (...) as is compatible with clarity of exposition. The techniques used are not only described but given a theoretical justification. Proofs of Consistency, Completeness and Independence are set out in detail. The fundamental characteristics of the various systems studies, and their relations to each other are established by meta-logical proofs, which are used freely in all sections of the book. Exercises are appended to most of the chapters, and answers are provided. (shrink)

This considerably revised second edition of Wittgenstein's 1914-16 notebooks contains a new appendix with photographs of Wittgenstein's original work, a new preface by Elizabeth Anscombe, and a useful index by E.D. Klemke. Corrections have been made throughout the text, and notes have been added, making this the definitive edition of the notebooks. The writings intersperse Wittgenstein's technical logical notations with his thoughts on the meaning of life, happiness, and death. "When the first edition of this collection of remarks appeared in (...) 1961 we were provided with a glimpse of the workings of Wittgenstein's mind during the period when the seminal ideas of the _Tractatus Logico-Philosophicus_ were being worked out. This second edition provided the occasion to be struck anew by the breadth, rigor, and above all the restlessness of that mind."—T. Michael McNulty, S. J., _The Modern Schoolman_. (shrink)

One of the ways of dividing all philosophers into two kinds is by saying of each whether he is an ordinary man's philosopher or a philosophers' philosopher. Thus Plato is a philosophers' philosopher and Aristotle an ordinary man's philosopher. This does not depend on being easy to understand: a lot of Aristotle's Metaphysics is immensely difficult. Nor does being a philosophers' philosopher imply that an ordinary man cannot enjoy the writings, or many of them. Plato invented and exhausted a form: (...) no one else has written such dialogues. So someone with no philosophical bent, or who has left his philosophical curiosity far behind may still enjoy reading some of them. (shrink)

There are methodological problems with the new techniques reviewed by Posner & Raichle. Some brain mechanisms are not detected by the temporal and spatial resolution. Questions are also raised by the stimulation paradigms.

Despite the periodic table having been discovered by chemists half a century before the discovery of electronic structure, modern designs are invariably based on physicists’ definition of periods. This table is a chemists’ table, reverting to the phenomenal periods that led to the table’s discovery. In doing so, the position of hydrogen is clarified.