: This paper examines the debate in the late 19th and early 20th centuries over the acceptability of atomic and molecular physics. It focuses on three prominent figures: Maxwell, who defended atomic physics, Ostwald, who initially rejected it but changed his mind as a result of experiments by Thomson and Perrin, and Duhem, who never accepted it. Each scientist defended the position he did in the light of strongly held methodological views concerning empirical evidence. The paper critically evaluates each of (...) these methodological positions. (shrink)
Recently in this journal Sherrilyn Roush (2004) defends positive relevance as a necessary (albeit not a sufficient) condition for evidence by rejecting two of the counterexamples from my earlier (2001) work. In this reply I argue that Roush's critique is not successful.
Is there a universal set of rules for discovering and testing scientific hypotheses? Since the birth of modern science, philosophers, scientists, and other thinkers have wrestled with this fundamental question of scientific practice. Efforts to devise rigorous methods for obtaining scientific knowledge include the twenty-one rules Descartes proposed in his Rules for the Direction of the Mind and the four rules of reasoning that begin the third book of Newton's Principia , and continue today in debates over the very possibility (...) of such rules. Bringing together key primary sources spanning almost four centuries, Science Rules introduces readers to scientific methods that have played a prominent role in the history of scientific practice. Editor Peter Achinstein includes works by scientists and philosophers of science to offer a new perspective on the nature of scientific reasoning. For each of the methods discussed, he presents the original formulation of the method selections written by a proponent of the method together with an application to a particular scientific example and a critical analysis of the method that draws on historical and contemporary sources. The methods included in this volume are Cartesian rationalism with an application to Descartes' laws of motion Newton's inductivism and the law of gravity two versions of hypothetico-deductivism -- those of William Whewell and Karl Popper -- and the nineteenth-century wave theory of light Paul Feyerabend's principle of proliferation and Thomas Kuhn's views on scientific values, both of which deny that there are universal rules of method, with an application to Galileo's tower argument. Included also is a famous nineteenth-century debate about scientific reasoning between the hypothetico-deductivist William Whewell and the inductivist John Stuart Mill and an account of the realism-antirealism dispute about unobservables in science, with a consideration of Perrin's argument for the existence of molecules in the early twentieth century. (shrink)
: In response to a charge of subjectivism, Kuhn in his Postscript emphasizes the importance of "values" (accuracy, simplicity, explanatory power, etc) that are shared by scientists generally. However, Kuhn adds, these values are applied differently by different scientists. By employing a comparison with partially subjective views of Carnap on confirming evidence, this paper raises questions about Kuhn's position on values by considering ways it might be interpreted as subjective and ways it may not.
What is required for something to be evidence for a hypothesis? In this fascinating, elegantly written work, distinguished philosopher of science Peter Achinstein explores this question, rejecting typical philosophical and statistical theories of evidence. He claims these theories are much too weak to give scientists what they want--a good reason to believe--and, in some cases, they furnish concepts that mistakenly make all evidential claims a priori. Achinstein introduces four concepts of evidence, defines three of them by reference to "potential" evidence, (...) and characterizes the latter using a novel epistemic interpretation of probability. The resulting theory is then applied to philosophical and historical issues. Solutions are provided to the "grue," "ravens," "lottery," and "old-evidence" paradoxes, and to a series of questions. These include whether explanations or predictions furnish more evidential weight, whether individual hypotheses or entire theoretical systems can receive evidential support, what counts as a scientific discovery, and what sort of evidence is required for it. The historical questions include whether Jean Perrin had non-circular evidence for the existence of molecules, what type of evidence J. J. Thomson offered for the existence of the electron, and whether, as is usually supposed, he really discovered the electron. Achinstein proposes answers in terms of the concepts of evidence introduced. As the premier book in the fabulous new series Oxford Studies in Philosophy of Science, this volume is essential for philosophers of science and historians of science, as well as for statisticians, scientists with philosophical interests, and anyone curious about scientific reasoning. (shrink)
There are two reasons, I claim, scientists do and should ignore standard philosophical theories of objective evidence: (1) Such theories propose concepts that are far too weak to give scientists what they want from evidence, viz., a good reason to believe a hypothesis; and (2) They provide concepts that make the evidential relationship a priori, whereas typically establishing an evidential claim requires empirical investigation.
An a priori thesis about evidence, defended by many, states that the only empirical fact that can affect the truth of an objective evidence claim of the form ‘e is evidence for h’ (or ‘e confirms h to degree r’) is the truth of e; all other considerations are a priori. By examining cases involving evidential flaws, I challange this claim and defend an empirical concept of evidence. In accordance with such a concept, whether, and the extent to which, e, (...) if true, confirms h is an empirical, not a priori, fact. (shrink)
Do predictions of novel facts provide stronger evidence for a theory than explanations of old ones? Sometimes yes, sometimes no. Which obtains has nothing to do with whether the evidence is predicted or explained, but only with the selection procedure used to generate the evidence. This is demonstrated by reference to a series of hypothetical drug cases and to Heinrich Hertz's 1883 cathode ray experiments.
According to a standard account of evidence, one piece of information is stronger evidence for an hypothesis than is another iff the probability of the hypothesis on the one is greater than it is on the other. This condition, I argue, is neither necessary nor sufficient because various factors can strengthen the evidence for an hypothesis without increasing (and even decreasing) its probability. Contrary to what probabilists claim, I show that this obtains even if a probability function can take these (...) evidential factors into account in ways they suggest and yield a unique probability value. Nor will the problem be solved by appealing to second-order probabilities. (shrink)
Laudan and Cantor maintain that there exists a methodological gulf between 19th century wave theorists of light, who employed a method of hypothesis, and 18th and 19th century particle theorists, who were inductivists. This paper examines how in fact wave theorists typically argued for their theory, in order to see to what extent their reasoning corresponds to the method of hypothesis or to inductivism in sophisticated versions of these doctrines offered by Whewell and Mill. It also examines how, given the (...) methodology they actually employed, wave theorists could in principle deal with anomalies to their theory, particularly with phenomena, such as dispersion, which their theory could not explain. (shrink)
This volume brings together eleven essays by the distinguished philosopher of science, Peter Achinstein. The unifying theme is the nature of the philosophical problems surrounding the postulation of unobservable entities such as light waves, molecules, and electrons. How, if at all, is it possible to confirm scientific hypotheses about "unobservables"? Achinstein examines this question as it arose in actual scientific practice in three nineteenth-century episodes: the debate between particle and wave theorists of light, Maxwell's kinetic theory of gases, and J.J. (...) Thomson's discovery of the electron. The book contains three parts, each devoted to one of these topics, beginning with an essay presenting the historical background of the episode and an introduction to the philosophical issues. There is an illuminating evaluation of various scientific methodologies, including hypothetico-deductivism, inductivism, and the method of independent warrant which combines features of the first two. Achinstein assesses the philosophical validity of both nineteenth-century and modern answers to questions about unobservables, and presents and defends his own solutions. (shrink)
By reference to Maxwell's kinetic theory, one feature of hypothetico-deductivism is defended. A scientist need make no inference to a hypothesis when he first proposes it. He may have no reason at all for thinking it is true. Yet it may be worth considering. In developing his kinetic theory there were central assumptions Maxwell made (for example, that molecules are spherical, that they exert contact forces, and that their motion is linear) that he had no reason to believe true. In (...) this paper I develop a position that explains why they were worth considering, and that rejects the retroductive position that a hypothesis is worth considering when, if true, it would explain the observed data. (shrink)
Theories of explanation are characterized as being either pragmatic or non-pragmatic, without a clear sense of what this is supposed to mean. The present paper offers a definition of a "pragmatic explanation-sentence", and in terms of this, of a "pragmatic theory of explanation". It is argued that van Fraassen's theory of explanation, despite claims to the contrary, is not genuinely pragmatic. By contrast, the author's own "illocutionary" theory is pragmatic. Attention is devoted particularly to sentences of the form "E is (...) a good explanation of q", which, it is urged, are pragmatic in a strong sense. In defense of this claim, and of the advantages of a pragmatic account generally, appeal is made to Rutherford's 1911 subatomic explanation of the results of his scattering experiments. Implications of a pragmatic theory are drawn for the debate between realists and anti-realists and absolutists and relativists. (shrink)
An examination of difficulties in three standard accounts of functions leads to the suggestion that sentences of the form "the function of x is to do y" are used to make a variety of different claims, all of which involve a means-end relationship and the idea of design, or use, or benefit. The analysis proposed enables us to see what is right and also wrong with accounts that analyze the meaning of function statements in terms of good consequences, goals, and (...) etiological explanation. It also enables us to show that function sentences can be used in providing various types of explanations, including, in certain cases, noncausal explanations of the presence of the item with the function. (shrink)