Anjan Chakravartty is a leading figure in various fields of contemporary philosophy. His research covers different issues in metaphysics and history and philosophy of science. He has stood out for his active participation in the debates about scientific realism and anti-realism. In a series of articles and in his book A Metaphysics for Scientific Realism: Knowing the Unobservable (2007) he has developed a defense of a position that he labeled ‘semirealism’, and for a related commitment to ‘dispositional realism’. In this framework he has addressed issues about the nature of dispositions, causation, laws of nature and natural kinds. Likewise, he has made significant contributions concerning scientific representation, modeling and related topics such as the function of abstraction and idealization. One of his most central concerns is the relationship between science and metaphysics, which is a fundamental topic of his last book Scientific Ontology: Integrating Naturalized Metaphysics and Voluntarist Epistemology (2017). Currently he is developing projects concerning the public understanding of science and science education, science and humanism, and related issues such as the epistemology of scientific disagreements.

The articles that compose the current special issue were presented at the V Workshop of the Circle of Buenos Aires ‘The Philosophy of Anjan Chakravartty: epistemology, ontology and scientific realism’, which took place at the University of Buenos Aires in October 2018. It comprises articles written by Rodolfo Gaeta, Nélida Gentile and Susana Lucero, Adriana Spehrs, and Bruno Borge. In addition, the section includes a paper by Tobias Henschen, written for this special issue. Each of the articles received a response and comments formulated by professor Chakravartty, who participated as a special guest of the event. The present monographic section includes those responses and comments.

In the article ‘Can Science Escape Metaphysics?’ Rodolfo Gaeta discusses one of Chakravartty’s most provocative theses: the idea that science cannot avoid the assumption of some metaphysical commitments. Chakravartty has remarked that both science and philosophy are engaged with ontological questions, so we have to ask if it is possible to have a scientific ontology that is independent of metaphysics. His answer to that question consists mainly in arguing that metaphysics is infused into science in two ways: through metaphysical presuppositions and through metaphysical inferences. The former generally remain implicit, while metaphysical inferences are instances of reasoning in which some a priori premises are used, whether implicitly or explicitly. These features are manifested through metaphysical considerations that, according to Chakravartty, scientists cannot escape when describing the ontology of the world. Gaeta analyses different meanings of the concept of ontology and metaphysics and, with the help of this analysis, examines Chakravartty’s arguments. He contrasts these arguments with some theses defended by several authors, in particular by empiricist philosophers who have tried to separate science from metaphysics, such as Carnap, Quine and van Fraassen. He concludes that the reasons given by Chakravartty in favour of the claim that the sciences cannot avoid metaphysics are insufficient.

In ‘On the explanatory power of dispositional realism’, Nélida Gentile and Susana Lucero critically examine two of the main virtues that Chakravartty attributes to dispositional realism. According to Chakravartty, his dispositional realism is a sort of selective realism that not only eludes criticisms formulated against structural realism as well as those formulated against entity realism, it also allows the unification of both versions of realism, generally conceived as incompatible. This unification constitutes the first virtue of dispositional realism claimed by Chakravartty. Thus, dispositional realism contributes to an intellectual framework that combines the best insights of both positions. The authors analyse the foundations of the alleged unification and conclude that it is not completely successful: on the one hand, dispositional realism does not overcome criticisms of entity realism; on the other hand, it sacrifices the heart of structural realism. Concerning the second virtue, it consists in the capacity of unifying three metaphysical concepts: causation, laws of nature and natural kinds; by these means, dispositional realism contributes to the plausibility and economy of realism. Against this thesis, Gentile and Lucero argue that the postulation of natural kinds is dispensable. They claim that causal powers and laws of nature are sufficient to do the work required by dispositional realism. Those two concepts jointly collaborate to give plausibility and economy to the position. On the contrary, the indispensability of natural kinds does not help to pursue that goal; it rather results in an ontological inflation. The authors defend a more deflationary conception of realism which can satisfy, without unnecessary inflation, the main demands of a scientific realist.

In ‘Dispositional realism, conflicting models and contrastive explanation’, Adriana Spehrs discusses Chakravartty’s arguments against the thesis of perspectivism. This position, which is sometimes presented as a form of realism, but which Chakravartty argues may amount to a form of antirealism, holds that we can only achieve a knowledge of perspectival facts, either because our epistemic abilities prevent us from knowing non-perspectival facts or because the latter do not exist. To argue against this view, Chakravartty offers his theory of Ontological Pluralism about Behavior which intends to solve, on the one hand, the problem of conflicting scientific models, and on the other hand, the problem of different descriptions arising from observations and alternative detection procedures. His project gives a response to these challenges by assuming that the properties represented by scientific models are dispositional properties; this thesis explains the fact that the objects which possess them behave in different ways under different circumstances; however, when considered by themselves, properties are not perspectival. Nor is there an impediment to finally achieving non-perspectival knowledge about the objects and systems that are investigated. Chakravartty supports his thesis by means of an analogy between the theory of contrastive explanations in answer to ‘why’ questions, and a proposed view of contrastive explanations that answer ‘what’ questions. Spehrs disputes his arguments, arguing that the definitions of ‘dispositional fact’ and ‘perspectival fact’ are imprecise and their application to concrete phenomena are fuzzy. In addition, she objects that the analogy drawn between contrastive explanations of ‘what’ questions and the corresponding explanations of ‘why’ questions lacks a sound foundation, since it is problematic to identify the contrast class in the former case. In sum, one cannot see how dispositional realism can amount to a refutation of perspectivism.

In ‘Disagreement about scientific ontology’, Bruno Borge addresses the question of epistemic disagreements between peers, that is to say, disagreements among subjects who have approximately the same evidence and the same cognitive virtues. The literature around this problem displays two main positions: the conciliatory view and the steadfast view. The former holds that, in cases of disagreement, it is rational that the agents adjust their beliefs in light of disagreement; whereas the latter claims that maintaining their original doxastic attitudes is the right thing to do. Borge’s analysis focuses on philosophical disagreements, more specifically in the field of scientific ontology. He argues that an adequate explanation of disagreements between peers, in the metaphysics of science, should consider the role of what he labels epistemic perspectives. This notion is closely linked with the notion of epistemic stances used by Chakravartty and that of epistemic systems used by Goldman. Borge characterizes an epistemic perspective as a set of epistemic polices oriented towards the achievement of some preferred epistemic goals, guided by specific values. The paper ends with an analysis of the metaphysics of laws of nature as a case study and the prospect of a collaborative epistemology that allows a trans-perspectival evaluation of different positions regarding scientific ontology.

In his article ‘Subatomic particles, epistemic stances, and Kantian antinomies’, Tobias Henschen discusses a neo-pyrrhonist view that Chakravartty argues is capable of deflating, in a sense, the conflict between the empiricist stance and the metaphysical stance. In view of a parity of rationality between each of these stances, the pyrrhonism suggested by Chakravartty advises that we may achieve ataraxia by suspending judgment or remaining speechless in the face of this isostheneia. Alternatively, Henschen proposes that we adopt a form of neo-kantianism, which would succeed in overcoming the conflict between metaphysics and empiricism without lapsing into pyrrhonism, as illustrated by means of a case study concerning the conflict between traditional metaphysics and structural realism.

In his article ‘On semirealism, realism more generally, and underlying epistemic stances’, Professor Chakravartty discusses all of the preceding issues and more, in response to the challenges presented by the authors in this special issue.

Rodolfo Gaeta

Nélida Gentile

Susana Lucero