•  221
    Physical theories continue to be interpreted in terms of particles. The idea of a particle required modification with the advent of quantum theory, but remains central to scientific explanation. Particle ontologies also have the virtue of explaining basic epistemic features of the world, and so remain appealing for the scientific realist. However, particle ontologies are untenable when coupled with the empirically necessary postulate of permutation invariance—the claim that permuting the roles o…Read more
  •  132
    No two entities without identity
    Synthese 181 (3): 433-450. 2011.
    In a naïve realist approach to reading an ontology off the models of a physical theory, the invariance of a given theory under permutations of its property-bearing objects entails the existence of distinct possible worlds from amongst which the theory cannot choose. A brand of Ontic Structural Realism attempts to avoid this consequence by denying that objects possess primitive identity, and thus worlds with property values permuted amongst those objects are really one and the same world. Assumin…Read more
  •  123
    Projection, symmetry, and natural kinds
    Synthese 192 (11): 3617-3646. 2015.
    Scientific practice involves two kinds of induction. In one, generalizations are drawn about the states of a particular system of variables. In the other, generalizations are drawn across systems in a class. We can discern two questions of correctness about both kinds of induction: what distinguishes those systems and classes of system that are ‘projectible’ in Goodman’s sense from those that are not, and what are the methods by which we are able to identify kinds that are likely to be projectib…Read more
  •  111
    Ontology & Methodology
    Synthese 192 (11): 3413-3423. 2015.
    Philosophers of science have long been concerned with the question of what a given scientific theory tells us about the contents of the world, but relatively little attention has been paid to how we set out to build theories and to the relevance of pre-theoretical methodology on a theory’s interpretation. In the traditional view, the form and content of a mature theory can be separated from any tentative ontological assumptions that went into its development. For this reason, the target of inter…Read more
  •  90
    The use of the Law of Likelihood (LL) as a general tool for assessing rival hypotheses has been criticized for its ambiguous treatment of background information. The LL endorses radically different answers depending on what information is designated as background versus evidence. I argue that once one distinguishes between two questions about evidentiary support, the ambiguity vanishes. I demonstrate this resolution by applying it to a debate over the status of the ‘fine-tuning argument’.
  •  77
    Scientists routinely solve the problem of supplementing one’s store of variables with new theoretical posits that can explain the previously inexplicable. The banality of success at this task obscures a remarkable fact. Generating hypotheses that contain novel variables and accurately project over a limited amount of additional data is so difficult—the space of possibilities so vast—that succeeding through guesswork is overwhelmingly unlikely despite a very large number of attempts. And yet scie…Read more
  •  71
    Peirce on the method of balancing 'likelihoods'
    Transactions of the Charles S. Peirce Society 45 (4). 2009.
    Framed as a critique of David Hume’s analysis of miracles, Peirce offers a sustained argument against an approach to historical inference he calls the “Method of Balancing Likelihoods‘ (MBL). In MBL the posterior probability that a disputed historical event has occurred is computed on the basis of the prior probability of that event occurring and the probability that each purported witness of the event has given accurate testimony. Peirce’s critique of this method is hierarchical: he denies that…Read more
  •  70
    Biological codes and topological causation
    Philosophy of Science 75 (3): 259-277. 2008.
    Various causal details of the genetic process of translation have been singled out to account for its privileged status as a ‘code'. We explicate the biological uses of coding talk by characterizing a class of special causal processes in which topological properties are the causally relevant ones. This class contains both the process of translation and communication theoretic coding processes as special cases. We propose a formalism in terms of graphs for expressing our theory of biological code…Read more
  •  58
    Entities Without Identity: A Semantical Dilemma
    Erkenntnis 84 (2): 283-308. 2019.
    It has been suggested that puzzles in the interpretation of quantum mechanics motivate consideration of entities that are numerically distinct but do not stand in a relation of identity with themselves or non-identity with others. Quite apart from metaphysical concerns, I argue that talk about such entities is either meaningless or not about such entities. It is meaningless insofar as we attempt to take the foregoing characterization literally. It is meaningful, however, if talk about entities w…Read more
  •  33
    Most attempts to answer the question of whether populations of groups can undergo natural selection focus on properties of the groups themselves rather than the dynamics of the population. Those approaches to group selection that do emphasize dynamics lack an account of the relevant notion of equivalent dynamics. I present a new approach to identifying instances of evolution by natural selection that is based upon dynamical symmetries. I apply the symmetry method to arrive at an affirmative but …Read more
  •  29
    The idea that the world is made of particles — little discrete, interacting objects that compose the material bodies of everyday experience — is a durable one. Following the advent of quantum theory, the idea was revised but not abandoned. It remains manifest in the explanatory language of physics, chemistry, and molecular biology. Aside from its durability, there is good reason for the scientific realist to embrace the particle interpretation: such a view can account for the prominent epistemic…Read more
  •  22
    Kinds of process and the levels of selection
    Synthese 196 (6): 2407-2433. 2019.
    Most attempts to answer the question of whether populations of groups can undergo natural selection focus on properties of the groups themselves rather than the dynamics of the population of groups. Those approaches to group selection that do emphasize dynamics lack an account of the relevant notion of equivalent dynamics. I show that the theory of ‘dynamical kinds’ I proposed in Jantzen :3617–3646, 2014) can be used as a framework for assessing dynamical equivalence. That theory is based upon t…Read more
  •  19
    I introduce a thin concept of ad hoc identity -- distinct from metaphysical accounts of either relative identity or absolute identity -- and an equally thin account of concepts and their content. According to the latter minimalist view of concepts, the content of a concept has behavioral consequences, and so content can be bounded if not determined by appeal to linguistic and psychological evidence. In the case of counting practices, this evidence suggests that the number concept depends on a no…Read more
  •  18
    The philosophy of science
    The Philosophers' Magazine 72 63-64. 2016.
  •  16
    The Fine Tuning Argument unmasked
    The Philosophers' Magazine 68 49-55. 2015.
  •  16
    Scientific Variables
    Philosophies 6 (4): 103. 2021.
    Despite their centrality to the scientific enterprise, both the nature of scientific variables and their relation to inductive inference remain obscure. I suggest that scientific variables should be viewed as equivalence classes of sets of physical states mapped to representations (often real numbers) in a structure preserving fashion, and argue that most scientific variables introduced to expand the degrees of freedom in terms of which we describe the world can be seen as products of an algorit…Read more
  •  8
    Dynamical Symmetries and Model Validation
    In James Robert Brown, Shaoshi Chen, Robert M. Corless, Ernest Davis, Nicolas Fillion, Max Gunzburger, Benjamin C. Jantzen, Daniel Lichtblau, Yuri Matiyasevich, Robert H. C. Moir, Mark Wilson & James Woodward (eds.), Algorithms and Complexity in Mathematics, Epistemology, and Science: Proceedings of 2015 and 2016 Acmes Conferences, Springer New York. pp. 153-176. 2019.
    I introduce a new method for validating models—including stochastic models—that gets at the reliability of a model’s predictions under intervention or manipulation of its inputs and not merely at its predictive reliability under passive observation. The method is derived from philosophical work on natural kinds, and turns on comparing the dynamical symmetries of a model with those of its target, where dynamical symmetries are interventions on model variables that commute with time evolution. I d…Read more
  •  4
    An Introduction to Design Arguments
    Cambridge University Press. 2014.
    The history of design arguments stretches back to before Aquinas, who claimed that things which lack intelligence nevertheless act for an end to achieve the best result. Although science has advanced to discredit this claim, it remains true that many biological systems display remarkable adaptations of means to ends. Versions of design arguments have persisted over the centuries and have culminated in theories that propose an intelligent designer of the universe. This volume is the only comprehe…Read more
  • Ch. 2. Peirce on miracles : the failure of Bayesian analysis
    In Jake Chandler & Victoria S. Harrison (eds.), Probability in the Philosophy of Religion, Oxford University Press. 2012.