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Department of History and Philosophy of Science


Paper manager: Matt Farr (Michaelmas Term), Hasok Chang (Lent & Easter Terms)

Also offered as an optional paper in Part IIB of the Human, Social and Political Sciences Tripos (HSPS) and Part IB of the Philosophy Tripos.

Michaelmas Term
Realism and Reductionism
Hasok Chang (4), Tim Lewens (4)
Fri 11am (weeks 1–8)
Laws of Nature
Anna Alexandrova (4)
Wed 12noon (weeks 1–4)
Jacob Stegenga (4)
Wed 12noon (weeks 5–8)
Lent Term
Realism and Reductionism (continued)
Hasok Chang (2), Tim Lewens (2)
Fri 11am (weeks 1–4)
Evidence, Explanation and Models
Marta Halina (4), Matt Farr (4)
Wed 10am (weeks 1–8)

This paper considers a series of central questions in the philosophy of science. Topics covered include whether we should believe that our best scientific theories are true, whether there are fundamental laws and what they might be, the role of various forms of simplification and idealisation in science, issues around the alleged unity of the sciences and of scientific method, and the relationship between scientific knowledge and practical interventions.

Aims and learning outcomes

  • to develop in students a broad understanding of central issues in the philosophy of science and to inform them on current issues in the philosophy of specific sciences;
  • to develop in students the ability to engage topics in science and medicine from multiple critical perspectives and develop their own views on current problems and debates;
  • to strengthen students' analytic writing and communication skills, especially in relation to topics in science and medicine.


Realism and Reductionism
Hasok Chang, Tim Lewens (12 lectures, Michaelmas & Lent Terms)

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.

  • Live discussion sessions on Teams on 6 November, 27 November and 12 February. Lectures are pre-recorded. Follow the links on Moodle.

Laws of Nature
Anna Alexandrova (4 lectures, Michaelmas Term)

The discovery and confirmation of laws have long been considered the crowning glory of modern science, but specifying exactly what these laws are has proved a thorny task. In this course, we consider three sides of the contemporary debate. The first side claims that laws are few and not nearly as important as first thought and instead science is after more modest and less universal truths such as mechanisms. The second side disagrees and defines laws as stemming from fundamental causal powers inherent in objects. The third side also believes in laws, but defines them as mere summaries of events that do not govern the world. We will evaluate these options by considering both their metaphysical presuppositions and their ability to make sense of methodology of science.

  • Live interactive session on Teams on 4 November. Lectures are pre-recorded. Follow the links on Moodle.

Jacob Stegenga (4 lectures, Michaelmas Term)

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.

  • Lectures are pre-recorded. Follow the links on Moodle.

Evidence, Explanation and Models
Marta Halina, Matt Farr (8 lectures, Lent Term)

There are many commonsense claims about science that enjoy wide acceptance. For example, that theories are supported by observations; that well-supported theories are more likely to be true; that scientists explain phenomena by accurately describing how they work. These claims have known problems, however. Observations are theory-laden, so it is not clear how they can be used to support theories in a non-circular way. Many well-supported theories have turned out to be false. Scientists sometimes explain phenomena using models that are intentionally distorting. Are there compelling accounts of scientific theory, models, evidence and explanation that overcome these problems? This series of lectures will address this and related questions, providing an introduction to key issues in philosophy of science.

  • Lectures 1 and 2 will be pre-recorded. Lectures 3 and 4 will be interactive sessions on Zoom. Follow the links on Moodle.

Preliminary reading

Resources for Paper 5 on Moodle