Leplin attempts to reinstate the common sense idea that theoretical knowledge is achievable, indeed that its achievement is part of the means to progress in empirical knowledge. He sketches the genesis of the skeptical position, then introduces his argument for Minimalist Scientific Realism -- the requirement that novel predicitons be explained, and the claim that only realism about scientific theories can explain the importance of novel prediction.

This title is part of UC Press's Voices Revived program, which commemorates University of California Press’s mission to seek out and cultivate the brightest minds and give them voice, reach, and impact. Drawing on a backlist dating to 1893, Voices Revived makes high-quality, peer-reviewed scholarship accessible once again using print-on-demand technology. This title was originally published in 1984.

Introduction Jarrett Leplin Hilary Putnam seems to have inaugurated a new era of interest in realism with his declaration that realism is the ...

Why be a scientific realist? The predominant motivation is explanationist: we need realism to understand the successfulness of science. Why be an antirealist? The predominant motivation is skeptical: theory systematically exceeds the reach of empirical warrant. Antirealists deny that explanatory power is evidential; realists deny that the reach of empirical warrant summarily terminates at the boundary of the observable. But these counterarguments are mere protection of philosophical stances to which the adversaries independently incline.

This book proposes an original theory of epistemic justification that offers a new way to relate justification to the epistemic goal of truth-conducive belief.

Objections to reliabilist theories of knowledge and justification have looked insuperable. Reliability is a property of the process of belief formation. But the generality problem apparently makes the specification of any such process ambiguous. The externalism of reliability theories clashes with strongly internalist intuitions. The reliability property does not appear closed under truth-preserving inference, whereas closure principles have strong intuitive appeal. And epistemic paradoxes, like the preface and the lottery, seem unavoidable if knowledge or justification depends on the frequency with (...) which a process generates true beliefs. The present theory has the conceptual resources to meet these challenges. It requires that a justificatory belief-formation process be intentionally applied. It distinguishes the justification of beliefs from that of the believer. And it avoids a frequency interpretation of reliability by introducing a notion of the normalcy of conditions under which processes are intentionally used. (shrink)

This paper criticizes the attempt to found the epistemological doctrine that all theories are evidentially underdetermined on the thesis that all theories have empirically equivalent rivals. The criticisms focus on the role of auxiliary hypotheses in prediction. It is argued, in particular, that if auxiliaries are underdetermined, then the thesis of empirical equivalence is undecidable. The inference from empirical equivalence to the underdetermination of total theories would seem to survive the criticisms, because total theories do not require auxiliaries to yield (...) observational consequences. It is shown that, nevertheless, underdetermination cannot be established for total theories. (shrink)

In response to recent recognition of the complexities of scientific change, discussion of the objectivity and the rationality of science has focused on criteria of theory choice. This paper addresses instead the rationality of scientific decisions at the level of ongoing research. It argues that whether or not a realist view of theories is compatible with the historical discontinuities of scientific change, certain realist assumptions are crucial to the rationality of research. The researcher must presume that questions about the existence (...) and the properties of at least some of the "unobservable" entities he theorizes about or experiments on are answerable on the basis of his work. The rationale of research cannot be understood solely in terms of the desiderata of instrumental utility or the empirical adequacy of theories. (shrink)

The fact that the goals and methods of science, as well as its empirical conclusions, are subject to change, is shown to allow at once for: (a) the objectivity of warrant for knowledge claims; (b) the absence of a priori standards from epistemology; (c) the normative character of epistemology; and (d) the rationality of axiological innovation. In particular, Laudan's attempt to make axiological constraints undercut epistemic realism is confuted.

This paper defends the Causal Theory of Reference against the recent criticism that it imposes a priori constraints on the aims and practices of science. The metaphysical essentialism of this theory is shown to be compatible with the requirements of naturalistic epistemology. The theory is nevertheless unable to forestall the problem of incommensurability for scientific terms, because it misrepresents the conditions under which their reference is fixed. The resources of the Causal Theory of Reference and of the traditional cluster or (...) "network" theory of meaning for handling problems of commensurability are compared, and an alternative approach is recommended. (shrink)

The point of the traditional distinction between the contexts of discovery and justification is to insist on the normative character of epistemology. The point is not to dismiss from epistemology merely the genesis of ideas; into the context of discovery go also descriptions of evaluative practices and decisions. However ideas are created, scrutinized, and judged, it is only the approbation to which they are entitled, accorded or not, that allegedly matters to epistemology. The criticism, familiar since N.R. Hanson's Patterns of (...) Discovery, that philosophy ought not to ignore the genesis of ideas is ironically conservative. If what is not normative epistemology is to be ignored, then the distinction would have us ignore even the reception and appraisal of scientific ideas. (shrink)

Pursuant to criticism, this paper revisits the relation between the theses of empirical equivalence and evidential underdetermination. I argue against some antirealist strategies for fixing the empirical commitments of underdetermined theories.

A realist interpretation of successful science is defended against a historical induction to the ultimate failure of current science from the failure of theories which once excelled by current standards. The defense requires (1) restrictions on the forms of success which realism, by its own lights, must explain, (2) referential stability through theory changes where the rejected theory achieves such success, and (3) degrees of truth for scientific statements.

The debate between realism and instrumentalism is at an impasse. That is the state of the art, and the competing positions and arguments are best understood by seeing how they have produced it. When scientists familiar with a common body of evidence, and with the resources of alternative theories for handling that evidence, nevertheless disagree as to which theory is best, something has gone wrong methodologically. Standards of evidential warrant, the criteria by which theories are to be judged, and not (...) just the theories themselves, are in dispute. When philosophers disagree about theories of science, without disputing the evidence brought to bear for or against the contenders, the legitimacy of standards of philosophical argument is similarly unresolved. In the debate over realism the central bone of contention is abductive inference. (shrink)

Karl Popper fut un réaliste scientifique malgré lui. Au mépris de ses propres restrictions concernant les formes de raisonnement scientifique acceptables et la portée de l’évidence empirique, il insista sur une conception fortement réaliste des buts et des accomplissements de la science. Dans cet article, je construis une défense générale du réalisme scientifique, m’appuyant, au il des développements, sur celles des positions popperiennes qui font progresser l’argument, et critiquant celles qui l’entravent. Bien que la ligne argumentative d’ensemble soit mienne, je (...) montre, par des attributions directes, que Popper partage mes conclusions réalistes, et pourquoi il les partage. (shrink)

Recent discussion of the problem of the conclusive falsification of scientific hypotheses has generally regarded the Duhemian Thesis (D-Thesis) as both true and interesting [10] but has dismissed the claim that disconfirmed hypotheses can be retained in explanations of the disconfirming evidence as either trivial [3] or unargued [12]. This paper rejects these positions. First, the status, in the argument for the D-Thesis, of the claim that auxiliary assumptions are necessary for the derivation of evidential propositions from hypotheses is examined. (...) It is concluded that depending on this status, the D-Thesis is either trivially true or unargued. Then the retention of contextually disconfirmed hypotheses is discussed. It is found that the use of such hypotheses in explanations of the disconfirming evidence is mediated by principles of scientific methodology. A new thesis is presented connecting the problem of conclusive falsification with changes in methodology. The argument for this thesis introduces a new analysis of methodological principles as inductive generalizations from scientific practice. Finally, the contribution of this analysis to the understanding of scientific change is described. (shrink)

Some recent theories in theoretical physics are not subject to epistemic evaluation by empiricist standards of evidential warrant. The advantage of these theories is not pragmatic but explanationist; they fail to yield testable consequences that distinguish them from earlier theories. But this is essentially a technological limitation, rather than a theoretical defect. There is an explanation, itself confirmed by empiricist standards, of the unconfirmability of these theories. This paper considers what epistemic stance is proper in this situation, and explores the (...) prospects for justifiable change to an explanationist methodology capable of warranting theories that transcend the range of our experience. (shrink)

Karl Popper fut un réaliste scientifique malgré lui. Au mépris de ses propres restrictions concernant les formes de raisonnement scientifique acceptables et la portée de l’évidence empirique, il insista sur une conception fortement réaliste des buts et des accomplissements de la science. Dans cet article, je construis une défense générale du réalisme scientifique, m’appuyant, au il des développements, sur celles des positions popperiennes qui font progresser l’argument, et critiquant celles qui l’entravent. Bien que la ligne argumentative d’ensemble soit mienne, je (...) montre, par des attributions directes, que Popper partage mes conclusions réalistes, et pourquoi il les partage. (shrink)

Australasian Journal of Philosophy, Volume 89, Issue 4, Page 738-740, December 2011.

Why be a scientific realist? The predominant motivation is explanationist: we need realism to understand the successfulness of science. Why be an antirealist? The predominant motivation is skeptical: theory systematically exceeds the reach of empirical warrant. Antirealists deny that explanatory power is evidential; realists deny that the reach of empirical warrant summarily terminates at the boundary of the observable. But these counterarguments are mere protection of philosophical stances to which the adversaries independently incline.