Philosophers’ traditional emphasis on theories, theoretical modeling, and explanation misguides research in philosophy of science. Articulating and applying core theories is part of scientific practice, but it is not the essence of scientific practice. Insofar as science has an essence, it is to systematically investigate and learn about what is not yet understood. This lecture analyzes genetics to articulate a broad-practice-centered approach to philosophy of science. It concludes by arguing that this approach can lead to richer, deeper, and more useful philosophies of science, philosophies that can better inform science policy and the public’s understanding of science.

I analyze the extent to which classical phase transitions, both first order and continuous, pose a challenge for intertheoretic reduction. My contention is that phase transitions are compatible with a notion of reduction that combines Nagelian reduction and what Thomas Nickles called Reduction2. I also argue that, even if the same approach to reduction applies to both types of phase transitions, there is a crucial difference in their physical treatment: in addition to the thermodynamic limit, in continuous phase transitions there is a second infinite limit involved, which marks an important difference in the reduction of first-order and continuous phase transitions.

Deidealization as a topic in its own right has attracted remarkably little philosophical interest despite the extensive literature on idealization. One reason for this is the often implicit assumption that idealization and deidealization are, potentially at least, reversible processes. We question this assumption by analyzing the challenges of deidealization within a menu of four broad categories: deidealizing as recomposing, deidealizing as reformulating, deidealizing as concretizing, and deidealizing as situating. On closer inspection, models turn out much more inflexible than the reversal thesis would have us believe, and deidealization emerges as a creative part of modeling.

Fictionalists believe that scientific models are about model systems that are imaginary. Michael Weisberg has claimed that fictionalism is indefensible because many scientific models are about model systems that are unimaginable. According to a certain account of imagination, what Weisberg says is plausible. According to another, more defensible account of imagination, it is not. I discuss these issues within the context of an allegedly unimaginable model system in ecology, but the conclusions I draw are more general. I then describe how fictionalism should be recast in order to deal with Weisberg’s critique.

John D. Norton’s “Material Theory of Induction” has been one of the most intriguing recent additions to the philosophy of induction. Norton’s account appears to be a notably natural account of actual inductive practices, although his theory (especially his answer to the Problem of Induction) has attracted considerable criticism. I detail several novel issues for his theory but argue that supplementing the Material Theory with a theory of direct inference could address these problems. I argue that if this combination is possible, a stronger theory of inductive reasoning emerges, which has a more propitious answer to the Problem of Induction.

Scientists often study hypotheses that they know to be false. This creates an interpretive problem for Bayesians because the probability assigned to a hypothesis is typically interpreted as the probability that the hypothesis is true. I argue that solving the interpretive problem requires coming up with a new semantics for Bayesian inference. I present and contrast two new semantic frameworks, and I argue that both of them support the claim that there is pervasive pragmatic encroachment on whether a given Bayesian probability assignment is rational.

In the current article and contrary to a widespread assumption, I argue that Humeanism and ontological emergence can peacefully coexist. Such a coexistence can be established by reviving elements of John Stuart Mill’s philosophy of science, in which an idiosyncratic account of diachronic emergence is associated with extensions of the Humean mosaic and the correlative coming into being of new best system laws, which have the peculiarity of being temporally indexed. Incidentally, this reconciliation of Humeanism and emergence allows for conceiving the autonomy of the special sciences in an interesting way, consistently with the reductionist ideal of a unified science.

This article develops and defends a new functional approach to scientific progress. I begin with a review of the problems of the traditional functional approach. Then I propose a new functional account of scientific progress, in which scientific progress is defined in terms of usefulness of problem defining and problem solving. I illustrate and defend my account by applying it to the history of genetics. Finally, I highlight the advantages of my new functional approach over the epistemic and semantic approaches and dismiss some potential objections to my approach.

This is one of a pair of discussion notes comparing some features of the account of causation in Wolfgang Spohn’s Laws of Belief with the “interventionist” account in James Woodward’s Making Things Happen. Despite striking similarities there are also important differences. These include (i) the “epistemic” orientation of Spohn’s account as opposed to the worldly or “ontic” orientation of the interventionist account, (ii) Spohn’s focus on token-level causal claims in contrast to the primary interventionist focus on type-level claims, (iii) the role of temporal information in accounting for causal asymmetry, and (iv) the extent to which causal claims are “frame relative.”

This is one of a pair of discussion notes comparing some features of the account of causation in Wolfgang Spohn’s Laws of Belief with the “interventionist” account in James Woodward’s Making Things Happen. This note locates the core difference of the accounts in the fact that Woodward’s account follows an epistemological order, while Spohn’s follows a conceptual order. This unfolds in five further differences: (i) type- versus token-level causation, (ii) reference to time, (iii) actual/counterfactual intervention versus epistemic/suppositional wiggling, (iv) a circular versus a circle-free conception of the circumstances of a direct causal relation, and (v) absolute versus model-relative causation.

Charlotte Werndl and Roman Frigg discuss the relationship between the Boltzmannian and Gibbsian framework of statistical mechanics, addressing, in particular, the question when equilibrium values calculated in both frameworks agree. This note points out conceptual confusions that could arise from their discussion, concerning, in particular, the authors’ use of “Boltzmann equilibrium.” It also clarifies the status of the Khinchin condition for the equivalence of Boltzmannian and Gibbsian equilibrium predictions and shows that it follows, under the assumptions proposed by Werndl and Frigg, from standard arguments in probability theory.

This article argues against Nina Emery’s view that there are compelling reasons to believe in nomological probabilities. To the degree that we can see no other way to detect the occurrence of the explanans apart from the bare fact that the explanandum happened, we may be skeptical that the proposed explanation is correct and open to the possibility that there is none. This provides us with a way to distinguish physical entities from mathematical ones, illuminating interpretations of quantum mechanics.