Philosophy of Science

University of Cambridge

 

about

I’m Matt, a philosopher of science based at the Department of History and Philosophy of Science and Wolfson College, at the University of Cambridge. I research philosophical problems about time and causality that arise in science, from fundamental physics to cognitive science, concerning the world itself and our ways of representing it. In particular I’m interested in what it means for time to have a direction.

On this site you’ll find open access versions of all my published work, information about my current and future research, details about my current teaching, and various other kinds of (ir)relevant info.

  • Dr Matt Farr is Associate Teaching Professor in the Department of History and Philosophy of Science at the University of Cambridge, and Fellow of Wolfson College, Cambridge. His research focuses on the nature of time and causation, particularly the directionality of time, the role of causality in physics, and the psychology of time and causation. Matt’s research has been published in philosophy journals such as the British Journal for the Philosophy of Science and Synthese, and he is currently writing a book on the philosophy and physics of time direction. Matt received his PhD in Philosophy from the University of Bristol, and has held postdoctoral research fellowships at the University of Sydney and University of Queensland.

  • Dr Matt Farr

    Department of History and Philosophy of Science, University of Cambridge, Free School Lane, Cambridge, CB2 3RH, United Kingdom.

    mail [AT] mattfarr [DOT] co [DOT] uk

 

 

current research

I’m interested in how science and metaphysics inform each other. What do scientific theories tell us about the nature of the world? How should metaphysics contribute to the understanding of scientific theories? And where do we go wrong in conflating metaphysical and empirical questions? I’ve written mainly about the directionality of time and the nature of causation, putting forward my own ‘C-theory of time’, according to which reality is fundamentally directionless.

My current research projects include the nature and role of global constraints in physics, and the notion of personhood across time and its role in medical ethics and psychiatry. These things, along with my child, are what keep me up at night.

Here are some of the main questions my research has addressed:

  • My work sets out and defends the ‘C-theory of time’: in short, time does not have a direction. My recent work defends a specific version of the C-theory, according to which our preference for describing the world as directed from past-to-future constitutes a convention motivated by the emergent causal structure of the world, but does not correspond to a deeper directedness of time. My work explores the consequences of directionless time for the metaphysics of causation, laws, chance, and modality more generally.

    Sample publications.

    • Farr, M. (2020). C‐theories of time: On the adirectionality of time. Philosophy Compass. [published version] | [preprint]

    • Farr, M. (2018). The ABC of Time. Aeon magazine. [published version]

    • Farr, M. (2022). Conventionalism about time direction. Synthese. [published version] | [preprint]

    • Farr, M. (2020). Causation and Time Reversal. British Journal for the Philosophy of Science. [published version] | [preprint]

    • Farr, M. (2022). What's so special about initial conditions? Understanding the past hypothesis in directionless time. To appear in Rethinking the Concept of Laws of Nature, ed. Y. Ben-Menahem. [preprint]

  • What is the status of causation in physics? It is common to provide causal explanations across the sciences, including physics. However, contemporary fundamental theories are ‘non-causal’ in a number of ways. For instance, the time symmetries of classical theories are prima facie at odds with the asymmetry of cause and effect, and the existence of non-local quantum correlations has led many to hold that quantum mechanics is non-causal in structure, or (alternatively) requires retrocausality. My work assesses the significance for causation of spatially and temporally non-local constraints, and defends ‘compatibilist’ accounts of causation; for instance, I’ve argued that the time symmetry of physical theories is perfectly compatible with a preferred direction of causation for physical systems.

    Sample publications.

  • Much of the metaphysics of time has relied on the idea that we perceive or experience time in a number of ways characteristic of popular temporal metaphysics. Against this tradition, my work sets out a ‘reductionist’ approach to the psychology of time, using empirical research in time and causality perception, and work in cognitive neuroscience, to address foundational issues concerning the passage of time, and the directionality of time and causation. My current work explores different ways in which the psychology and philosophy of time and causation relate, for instance what it means to perceive the direction of time, and in what sense our beliefs about cause and effect affect our perception of the time order of events. Much of this work is heavily empirical in nature, incorporating research in psychophysics and establishing the relationship between empirical work and the philosophy of time and causation.

    Sample Publications.

    • Farr, M. (2020). Explaining temporal qualia. European Journal of Philosophy of Science. [published version] | [preprint]

    • Farr, M. (2022). Perceiving direction in directionless time. In Understanding Human Time, ed. K. Jaczszolt. [preprint]

    • Farr, M. (2023). The three-times problem: Commentary on ‘Human time within physical time’. Frontiers in Psychology. [published version] | [preprint]

    • Baron, S., Cusbert, J., Farr, M., Kon, M. & K. Miller (2015). Temporal Experience, Temporal Passage and the Cognitive Sciences. Philosophy Compass. [published version]

 

 

recent publications

[see full list of publications]

  • [article] | [preprint]

    Invited essay for Institute of Arts & Ideas.

  • [published version] | [preprint]

    Frontiers in Psychology, vol. 14.

    Invited commentary on ‘Physical Time Within Human Time’.

  • [preprint] | [link to book]

    In Understanding Human Time, Oxford University Press, ed. K. M. Jaszczolt.

    Abstract. Modern physics has provided a range of motivations for holding time to be fundamentally undirected. But how does a temporally adirectional metaphysics, or ‘C-theory’ of time, fit with the time of experience? In this chapter, I look at what kind of problem human time poses for C-theories. First, I ask whether there is a ‘hard problem’ of human time: whether it is in principle impossible to have the kinds of experience we do in a temporally adirectional world. Second I consider the ‘easy problem’: how specific directed aspects of our temporal experience are to be explained by C-theorists. This leads to a greater issue: is there such a thing as an experience of time direction at all to even be explained? I show how the kinds of experience we have that we typically associate with the idea of time being directed can be accommodated within a directionless picture of time.

  • [published version] | [preprint]

    In Rethinking the Concept of Laws of Nature, Springer, ed. Y. Ben-Menahem.

    Abstract. It is often said that the world is explained by laws of nature together with initial conditions. But does that mean initial conditions don’t require further explanation? And does the explanatory role played by initial conditions entail or require that time has a preferred direction? This chapter looks at the use of the ‘initialness defence’ in physics, the idea that initial conditions are intrinsically special in that they don’t require further explanation, unlike the state of the world at other times. Such defences commonly assume a primitive directionality of time to distinguish between initial and final conditions. Using the case study of the time-asymmetry of thermodynamics and the so-called ‘past hypothesis’ — the hypothesis that the early universe was in a state of very low entropy —, I outline and support a deflationary account of the initialness defence that does not presuppose a basic directionality of time, and argue that there is a relevant explanatory asymmetry between initial conditions and the state of systems at other times only if certain causal conditions are satisfied. Hence, the initialness defence is available to those who reject a fundamental direction of time.

  • [published version] | [preprint]

    Synthese, 200, 23 (2022).

    Abstract. In what sense is the direction of time a matter of convention? In 'The Direction of Time', Hans Reichenbach makes brief reference to parallels between his views about the status of time’s direction and his conventionalism about geometry. In this article, I: (1) provide a conventionalist account of time direction motivated by a number of Reichenbach’s claims in the book; (2) show how forwards and backwards time can give equivalent descriptions of the world despite the former being the ‘natural’ direction of time; and (3) argue that this offers an important middle-ground position between existing realist and antirealist accounts of the direction of time.

  • [published version] | [preprint]

    Mind, 2021.

    Intro. Whatever you think of Bertrand Russell’s famous claim that the ‘law of causality’ is (at least as of 1912) redundant in the ‘advanced sciences’, it is nonetheless the case that a variety of concepts tangled up with the idea of causation — such as determinism and locality — remain ubiquitous within physics and elsewhere across the sciences. Yemima Ben-Menahem’s excellent book, Causation in Science, focuses not on reductive metaphysical accounts of these notions but instead on the roles they play within physics, and the relationships that hold between them, through a series of detailed historical case studies…

  • [published version] | [preprint]

    Philosophy Compass, 2020.

    Abstract. “The universe is expanding, not contracting.” Many statements of this form appear unambiguously true; after all, the discovery of the universe’s expansion is one of the great triumphs of empirical science. However, the statement is time-directed: the universe expands towards what we call the future; it contracts towards the past. If we deny that time has a direction, should we also deny that the universe is really expanding? This article draws together and discusses what I call ‘C-theories’ of time — in short, philosophical positions that hold time lacks a direction — from different areas of the literature. I set out the various motivations, aims, and problems for C-theories, and outline different versions of antirealism about the direction of time.

  • [published version] | [preprint]

    British Journal for Philosophy of Science, vol. 71. issue 1, March 2020, pp. 177–20, doi.org/10.1093/bjps/axx025

    Abstract. What would it be for a process to happen backwards in time? Would such a process involve different causal relations? It is common to understand the time-reversal invariance of a physical theory in causal terms, such that whatever can happen forwards in time (according to the theory) can also happen backwards in time. This has led many to hold that time-reversal symmetry is incompatible with the asymmetry of cause and effect. This article critiques the causal reading of time reversal. First, I argue that the causal reading requires time-reversal-related models to be understood as representing distinct possible worlds and, on such a reading, causal relations are compatible with time-reversal symmetry. Second, I argue that the former approach does, however, raise serious sceptical problems regarding the causal relations of paradigm causal processes and as a consequence there are overwhelming reasons to prefer a non-causal reading of time reversal, whereby time reversal leaves causal relations invariant. On the non-causal reading, time-reversal symmetry poses no significant conceptual nor epistemological problems for causation.

  • [published version] | [preprint]

    European Journal of Philosophy of Science, 2020, 10: 8; doi.org/10.1007/s13194-019-0264-6.

    Abstract. Experiences of motion and change are widely taken to have a ‘flow-like’ quality. Call this ‘temporal qualia’. Temporal qualia are commonly thought to be central to the question of whether time objectively passes: (1) passage realists take temporal passage to be necessary in order for us to have the temporal qualia we do; (2) passage antirealists typically concede that time appears to pass, as though our temporal qualia falsely represent time as passing. I reject both claims and make the case that passage-talk plays no useful explanatory role with respect to temporal qualia, but rather obfuscates what the philosophical problem of temporal qualia is. I offer a ‘reductionist’ account of temporal qualia that makes no reference to the concept of passage and argue that it is well motivated by empirical studies in motion perception.

  • [published version] | [preprint]

    Co-authored with Milena Ivanova (Cambridge).

    Routledge Handbook of Metametaphysics, 2020; , eds. R. Bliss & J.T.M. Miller. Routledge.

    Abstract. While science is taken to differ from non-scientific activities in virtue of its methodology, metaphysics is usually defined in terms of its subject matter. However, many traditional questions of metaphysics are addressed in a variety of ways by science, making it difficult to demarcate metaphysics from science solely in terms of their subject matter. Are the methodologies of science and metaphysics sufficiently distinct to act as criteria of demarcation between the two? In this chapter we focus on several important overlaps in the methodologies used within science and metaphysics in order to argue that focusing solely on methodology is insufficient to offer a sharp demarcation between metaphysics and science, and consider the consequences of this for the wider relationship between science and metaphysics.

 

 

current teaching

In the 2023-24 academic year I’m running the following undergraduate courses.

  • Part II, Paper 5 course. Co-taught with Hasok Chang.

    Description. Those who admire the achievements of modern science tend to express their admiration along the lines of scientific realism: scientific theories could only be so successful if they give us a really true account of nature. Scientific realists also commonly take a reductionist view: everything is ultimately made up of elementary particles, so all of our successful scientific theories must ultimately boil down to fundamental physics. In this course we will subject these popular views to close philosophical scrutiny, with reference to various specific cases in the physical and the biological sciences.

  • Part II, Paper 5 course. Michaelmas term.

    Description. Probability is fundamental to many aspects of sciences, including statistics, explanation, causation and hypothesis confirmation. This short series of lectures will begin by examining the nature of probability. We then turn to a basic formalisation of probability. Finally, we study the role of probability in fundamental scientific notions such as explanation and causation.

  • Part II ‘Primary Source’ seminar series

  • Part II course. Lent Term, weeks 1-4.

    Description. Modern physics has forced us to reconsider many of our basic concepts about the nature of reality. Relativity theory has led to new understandings of the nature of time and the relationship between time and space, and quantum mechanics appears to suggest that nature is neither deterministic, local or causal. This course focuses on whether and how physical theories should inform our metaphysics. Each lecture addresses a different metaphysical question and how it has been informed by developments in the foundations of classical, relativistic, quantum and statistical physics.

  • Part II course. Lent term, weeks 1-4.

    Description. Philosophy of psychiatry stands at the intersection of philosophy of medicine, philosophy of psychology, and philosophy of mind. This course considers various topics within philosophy of psychiatry, focusing on how the study of psychopathology interacts with the study of mind and brain. We will consider several key questions, including: What are mental disorders? Are they disorders of mind, brain, or society? How are conceptualisations of mental disorder influenced by culture? How are they influenced by developments in neuroscience? Is there such a thing as a “normal” mind? What can psychopathology tell us about “normal” mental functioning?

  • Part IB course. Lent term, weeks 5-8.

    Description. Modern physics paints a picture of the world that differs radically from our everyday conceptions. This course introduces you to the philosophical foundations of physics and the two-way relationship between physics and philosophy. What does physics really imply about the nature of the world we live in? What kinds of things are space and time? Could we travel into the past? How can we have knowledge of unobservable entities ranging from superstrings to the structure of the universe itself? And should we really trust the ever-changing theories that science gives us? We will examine these questions and more through a series of case studies from the history of physics.

I am also available to supervise undergraduate dissertations and MPhil essays/dissertations on the philosophy of science, metaphysics, and philosophy of mind in both the History and Philosophy of Science Department and Philosophy Faculty at Cambridge.

 

upcoming talks

 
  • Backwards Teleology and the Improbable Past.

    May 9-10, 2024. Time, Chance and Causation workshop, University of Stirling.

  • Is Time Directionless?

    May 14, 2024. Pint of Science festival, Cambridge.

  • From Time to Spacetime to No Time? The Philosophy of Relativity Theory.

    June 1, 2024. Philosophy of Cosmology workshop, St Cross Centre for the History and Philosophy of Physics, University of Oxford. [details]

 
 

 

media

Here are some recent-ish recordings of me presenting and discussing my research.

A podcast on which I participated in 2021, in which I discuss my C-theory of time.

A talk from 2018 at the London School of Economics.

 

oddities

My Erdös number is 5: Erdös → Anderson → Binmore → Paternotte → Ivanova → Me.

Had I been less interested in counterfactuals, I'd probably make my living as a drummer.

I’m an amateur latte artist and coffee snob.

Possibly as a result of a mid-life crisis, I’m now into running marathons.