NG van Kampen is a well-known theoretical physicist who has had a long and distinguished career. His research covers scattering theory, plasma physics, statistical mechanics, and various mathematical aspects of physics. In addition to his scientific work, he has written a number of papers about more general aspects of science. An indefatigable fighter for intellectual honesty and clarity, he has pointed out repeatedly that the fundamental ideas of physics have been needlessly obscured. As those papers appeared in various journals, (...) partly in Dutch, it was felt that it would be worthwhile to collect them and make them available to a larger audience. This is a book of major importance to scientists and university teachers. (shrink)

Theoretical determinism, as it is usually ascribed to Laplace, is neither verifiable nor falsifiable and has therefore no real content. It is not the same as predictability of actually observable phenomena. On the other hand, predictability is not an abstract principle; rather it is true to a certain degree, depending on the phenomena considered. It can be discussed only by examining the scientific state of affairs. This is done in some detail for classical statistical mechanics. Much of a recently published (...) debate on determinism is thereby obviated. (shrink)

Theoretical determinism, as it is usually ascribed to Laplace, is neither verifiable nor falsifiable and has therefore no real content. It is not the same as predictability of actually observable phenomena. On the other hand, predictability is not an abstract principle; rather it is true to a certain degree, depending on the phenomena considered. It can be discussed only by examining the scientific state of affairs. This is done in some detail for classical statistical mechanics. Much of a recently published (...) debate on determinism (Amsterdamski et al. 1990) is thereby obviated. (shrink)

Rapid developments in Artificial Intelligence are leading to an increasing human reliance on machine decision making. Even in collaborative efforts with Decision Support Systems, where a human expert is expected to make the final decisions, it can be hard to keep the expert actively involved throughout the decision process. DSSs suggest their own solutions and thus invite passive decision making. To keep humans actively ‘on’ the decision-making loop and counter overreliance on machines, we propose a ‘reflection machine’. This system asks (...) users questions about their decision strategy and thereby prompts them to evaluate their own decisions critically. We discuss what forms RMs can take and present a proof-of-concept implementation of a RM that can produce feedback on users’ decisions in the medical and law domains. We show that the prototype requires very little domain knowledge to create reasonably intelligent critiquing questions. With this prototype, we demonstrate the technical feasibility to develop RMs and hope to pave the way for future research into their effectiveness and value. (shrink)

Peacemakers as children of God : A pragmatic-linguistic reading. The article investigates different options of the pragmatic meaning of the beatitude in the Gospel of Matthew, ‘blessed are the peacemakers, for they shall be called children of God’. It also explores this Jesus logion’s seemingly contradiction with Jesus’ remark in die Matthean mission discourse, ‘Do not think that I have come to bring peace on earth; I have not come to bring peace, but a sword’. The pragmatic use of the (...) concept ‘peace’ in Matthew is probed against the background of scribal activity in the context of the restoration of villages in north-Galilee and south-Syria after the destruction of the temple in Jerusalem by the Romans. The pax Romana and Josephus’ appeal to the inhabitants of these villages to collaborate with the Romans is described as the context of these Matthean Jesus-logia. It argues that Matthew interprets Jesus as a ‘Mosaic Joshua’ in continuum with the Judaic tradition of Solomon as the ‘king of peace’, especially 1 Chronicles 22:5-11. The macarism about the ‘peacemakers as children of God’ is interpreted in correlation with the macarism ‘blessed are those who mourn, for they shall be comforted’. The article concludes with the finding that the sword-motif in Matthew 10:4 does not contradict the beatitude on peace in Matthew 5:9. (shrink)

SummaryIntense, sustained nursing lengthens inter-birth intervals and is causally linked with low natural fertility. However, in traditional settings, the effects of such nursing on fertility are difficult to disentangle from those of nutrition. Results from an prospective, direct observational study of reproductive function in well-nourished Amele women who nurse intensively and persistently but who also have high fertility are here presented. Endocrine measures show that ovarian activity resumes by median 11·0 months postpartum. Median duration of postpartum amenorrhoea is 11·3 months, (...) time to next conception is 19·0 months, and the inter-birth interval is 28·0 months. Average life time fertility is 6·8. High fertility in Amele women is due both to refractoriness of reproductive function to suckling stimuli, and to maintenance of equivalent age-specific fertility rates across the reproductive life span. (shrink)

Peacemakers as children of God : A pragmatic-linguistic reading. The article investigates different options of the pragmatic meaning of the beatitude in the Gospel of Matthew, ‘blessed are the peacemakers, for they shall be called children of God’. It also explores this Jesus logion’s seemingly contradiction with Jesus’ remark in die Matthean mission discourse, ‘Do not think that I have come to bring peace on earth; I have not come to bring peace, but a sword’. The pragmatic use of the (...) concept ‘peace’ in Matthew is probed against the background of scribal activity in the context of the restoration of villages in north-Galilee and south-Syria after the destruction of the temple in Jerusalem by the Romans. The pax Romana and Josephus’ appeal to the inhabitants of these villages to collaborate with the Romans is described as the context of these Matthean Jesus-logia. It argues that Matthew interprets Jesus as a ‘Mosaic Joshua’ in continuum with the Judaic tradition of Solomon as the ‘king of peace’, especially 1 Chronicles 22:5-11. The macarism about the ‘peacemakers as children of God’ is interpreted in correlation with the macarism ‘blessed are those who mourn, for they shall be comforted’. The article concludes with the finding that the sword-motif in Matthew 10:4 does not contradict the beatitude on peace in Matthew 5:9. (shrink)

Within ZFC, we develop a general technique to topologize trees that provides a uniform approach to topological completeness results in modal logic with respect to zero-dimensional Hausdorff spaces. Embeddings of these spaces into well-known extremally disconnected spaces then gives new completeness results for logics extending S4.2.

It is a landmark theorem of McKinsey and Tarski that if we interpret modal diamond as closure, then \ is the logic of any dense-in-itself metrizable space. The McKinsey–Tarski Theorem relies heavily on a metric that gives rise to the topology. We give a new and more topological proof of the theorem, utilizing Bing’s Metrization Theorem.

We prove that the existence of a measurable cardinal is equivalent to the existence of a normal space whose modal logic coincides with the modal logic of the Kripke frame isomorphic to the powerset of a two element set.