In the last three decades several cosmological principles and styles of reasoning termed 'anthropic' have been introduced into physics research and popular accounts of the universe and human beings' place in it. I discuss the circumstances of 'fine tuning' that have motivated this development, and what is common among the principles. I examine the two primary principles, and find a sharp difference between these 'Weak' and 'Strong' varieties: contrary to the view of the progenitors that all anthropic principles represent a (...) departure from Copernicanism in cosmology, the Weak Anthropic Principle is an instance of Copernicanism. It has close affinities with the step of Copernicus that Immanuel Kant took himself to be imitating in the 'critical' turn that gave rise to the Critique of Pure Reason. I conclude that the fact that a way of going about natural science mentions human beings is not sufficient reason to think that it is a subjective approach; in fact, it may need to mention human beings in order to be objective. (shrink)

Perhaps no term in the geological lexicon excites more passions than uniformitarianism, whose motto is “the present is the key to the past.” The term is controversial in part because it contains several meanings, which have been implicated in creating a situation of “semantic chaos” in the geological literature. Yet I argue that debates about uniformitarianism do not arise from a simple chaos of meanings. Instead, they arise from legitimate disagreements about substantive questions. This paper examines these questions and relates (...) them to several “forms of understanding” pursued by researchers in geohistory. (shrink)

I discuss how modern cosmology illustrates underdetermination of theoretical hypotheses by data, in ways that are different from most philosophical discussions. I confine the discussion to the history of the observable universe from about one second after the Big Bang, as described by the mainstream cosmological model: in effect, what cosmologists in the early 1970s dubbed the ‘standard model’, as elaborated since then. Or rather, the discussion is confined to a (very!) few aspects of that history. I emphasize that despite (...) the underdetermination, a scientific realist can, and should, endorse this description. (shrink)

During the last decade new developments in theoretical and speculative cosmology have reopened the old discussion of cosmology's scientific status and the more general question of the demarcation between science and non-science. The multiverse hypothesis, in particular, is central to this discussion and controversial because it seems to disagree with methodological and epistemic standards traditionally accepted in the physical sciences. But what are these standards and how sacrosanct are they? Does anthropic multiverse cosmology rest on evaluation criteria that conflict with (...) and go beyond those ordinarily accepted, so that it constitutes an “epistemic shift” in fundamental physics? The paper offers a brief characterization of the modern multiverse and also refers to a few earlier attempts to introduce epistemic shifts in the science of the universe. It further discusses the several meanings of testability, addresses the question of falsifiability as a sine qua non for a theory being scientific, and briefly compares the situation in cosmology with the one in systematic biology. Multiverse theory is not generally falsifiable, which has led to proposals from some physicists to overrule not only Popperian standards but also other evaluation criteria of a philosophical nature. However, this is hardly possible and nor is it possible to get rid of explicit philosophical considerations in some other aspects of cosmological research, however advanced it becomes. (shrink)

While Karl Popper’s philosophy of science has only few followers among modern philosophers, it is easily the view of science with the biggest impact on practicing scientists. According to Peter Medawar, Nobel laureate and eminent physiologist, Popper was the greatest authority ever on the scientific method. He praised the “great strength of Karl Popper’s conception of the scientific process,” a main reason for the praise being “that it is realistic—it gives a pretty fair picture of what goes on in real (...) life laboratories” (Medawar 1990, p. 100). Either explicitly or (more often) implicitly, many scientists subscribe to some version of simplified Popperianism, usually by adopting the demarcation criterion that a .. (shrink)

Problems of scientific cosmology only rarely occur in the works of Karl Popper. Nevertheless, it was a subject that interested him and which he occasionally commented on. What is more important, his general claim of falsifiability as a criterion that demarcates science from non-science has played a significant role in periods of the development of modern physical cosmology. The paper examines the historical contexts of the interaction between cosmology and Popperian philosophy of science. Apart from covering Popper’s inspiration from Einstein (...) and his views on questions of cosmology, it focuses on the impact of his thoughts in two periods of controversy of modern cosmology, the one related to the steady state theory and the other to the recent multiverse proposal. It turns out that the impact has been considerable, and continues to be so, but also that the versions of Popperian methodology discussed by cosmologists are sometimes far from what Popper actually thought and wrote. (shrink)

Modern standard big bang cosmology was preceded by a 15-year controversy with the rival steady-state theory of the universe. At a time when cosmologically relevant observations were scarce and cosmology was widely regarded as an immature science, or not a science at all, much of the debate took place by means of arguments that were essentially philosophical. Remarkably, professional philosophers, including some of the key figures of Anglo-American philosophy of science, took an active part in the debate; no less remarkably, (...) the involved astronomers and physicists sometimes listened to them. This article reviews the controversy over the steady-state theory as seen from the perspective of contemporary philosophy of science and offers an appraisal of how and to what extent philosophers and scientists entered a dialogue. -/- . (shrink)

During the last decade new developments in theoretical and speculative cosmology have reopened the old discussion of cosmology’s scientific status and the more general question of the demarcation between science and non-science. The multiverse hypothesis, in particular, is central to this discussion and controversial because it seems to disagree with methodological and epistemic standards traditionally accepted in the physical sciences. But what are these standards and how sacrosanct are they? Does anthropic multiverse cosmology rest on evaluation criteria that conflict with (...) and go beyond those ordinarily accepted, so that it constitutes an “epistemic shift” in fundamental physics? The paper offers a brief characterization of the modern multiverse and also refers to a few earlier attempts to introduce epistemic shifts in the science of the universe. It further discusses the several meanings of testability, addresses the question of falsifiability as a sine qua non for a theory being scientific, and briefly compares the situation in cosmology with the one in systematic biology. Multiverse theory is not generally falsifiable, which has led to proposals from some physicists to overrule not only Popperian standards but also other evaluation criteria of a philosophical nature. However, this is hardly possible and nor is it possible to get rid of explicit philosophical considerations in some other aspects of cosmological research, however advanced it becomes. (shrink)