The Durham Emergence Project brought together philosophers and physicists in a uniquely integrated research environment to deepen understanding of the possibility of strong emergence, and of candidate examples. The project’s research encompassed foundational work in metaphysics, to help clarify what strong emergence would be, were it to exist. It included work in the philosophy of mind, to develop new emergentist models of mental causation, as well as research in the philosophy of science questioning the evidence for the completeness of physics, because completeness rules out the possibility of strong emergence. This principle is widely accepted by philosophers and physicists, even though explicit arguments for it are rare. The project’s research also encompassed theoretical and experimental work in physics, advancing understanding of emergent states of particular magnetic materials, and developing new theoretical approaches to understanding the structure of materials and the application of renormalisation group methods.
The aims of the project were to critically examine and clarify both sides of the debate on emergence as it currently exists in the philosophy of mind, the philosophy of science, and in condensed matter physics, by addressing a central set of research questions spanning those fields. These aims have been fully achieved. Central to this success has been the development of a fully integrated research environment in which philosophers and physicists can (i) acquire concepts, theories and methods from another discipline; (ii) use this learning to enhance their understanding of the emergence debate in the context of their own discipline; and (iii) come to an agreement on how to apply philosophical concepts, such as that of emergence, in ways that allow interdisciplinary investigation and debate about them to proceed fruitfully, without the need for anything more than a very abstract definition. This allows that debates about different cases of emergence may proceed quite in quite distinct ways.
Our initial project overview can be viewed here. The summary below concentrates on the findings of the main Durham project team.
Metaphysics and philosophy of mind
Alex Carruth has investigated how issues in fundamental ontology bear on the possibility of an emergent mind and on arguments for the distinctness of mind and body. One application has been to the conceivability of so-called ‘zombies’ (animate human beings lacking consciousness). Sophie Gibb has developed an emergent theory of mind involving a new model of psychophysical causal relevance, based on the powers theory of causation, which she refers to as the ‘double prevention model’. She has also critically examined various formulations of the completeness (or closure) of physics, and its role in arguments for the causal exclusion of the mental. Matthew Tugby has developed a property-driven view of modality that he calls 'qualitative dispositionalism', which has converged with Mark Pexton’s work on contextual emergence, helping Pexton to develop new ways of thinking about the modal aspects of emergence.
Philosophy of Science
Nancy Cartwright has defended strong emergence as a metaphysical possibility, arguing that nature is ‘radically contingent’. The local kinds of regularity investigated by condensed matter physics and the special sciences are supported by specific powers and mechanisms, rather than being consequences of abstract and general laws, or long-past events such as the big bang. Robin Hendry has critically examined the scientific evidence for the completeness (or closure) of physics. Taking organic chemistry as an example, he has argued against the view that successful mechanistic explanation supports reductionism. He has also identified candidate examples of emergence in chemistry: defending the posibility that chemical substances emerge from their molecular constituents, and that molecular structures themselves emerge from the dynamical states of their constituent particles. Mark Pexton has critically examined information as a basis for defining strong emergence, and applied and developed the idea of contextual emergence to key examples in physics such as shock waves and (in collaborative work with Tom Lancaster and Tom McLeish), the fractional quantum Hall effect, and long-range topological order in entangled polymer rings.
Stewart Clark, Tom Lancaster and Iorwerth Thomas have worked on first-principles computations on molecular magnets, to identify the use of density functional theory in analysing and identifying emergent behavior in real systems; and also on computational methods to identify skyrmion lattices in magnets which provide an example of an emergent ordered phase of topological objects. With Robert Schoonmaker, Lancaster has attempted to identify aspects of emergent magnetism and superconductivity in the antiferromagnet FeAs, and has also collaborated with Tom McLeish and Mark Pexton in identifying specific cases of strong emergence in physics, and more generally on how to understand the use of the renormalization group in condensed matter physics. McLeish has identified specific cases of top-down causation in complex physical systems including the behaviour of large molecules and evolutionary constraints on development.