Part-whole relations within the fundamental potentialities in nature
Philosophy of Physics
Leverhulme Trust Research Project Grant
The project in brief
Potentialities (such as the elementary potentiality for spin) account for what things are and can do, as active or passive agents of change. What things can do and what can happen to them is complex. But potentialities are assumed, without further investigation, to be atomic (simple, indivisible, without parts). However, if potentiality is simple, how can it have a complex manifestation? Where does its complexity derive from? Furthermore, our current way of defining them in terms of their manifestation does not enable us to discover their internal structure, but keeps them ‘ghostly’ and elusive, behind the veil of their manifestation.
One reads, for example, on the webpage of the Hutchinson Cancer Research Center that there are ‘several approaches that Hutchinson researchers have developed to harness the power of the immune system as a weapon against [many types of] cancer’. Consider: what is the potentiality of the immune system, and how can it perform the multiple functions attributed to it? If it is simple, how can it have such diverse conditions of activation, and how can it perform such diverse types of function (corresponding to fighting different types of cancer)? Can it be that it is a complex potentiality – not many compresent potentialities, but a singular complex one? This supposition runs against the mainstream understanding of potentialities, according to which a potentiality is defined by one (and one only) type of manifestation it can have (e.g. Lowe 2009). On the other hand, if the potentiality of the immune system is complex, how is its complexity structured in its constitution? We do not have any theories concerning how potentialities partition, in order to even articulate this thought. Can, perhaps, thinking of such potentialities as being ‘multi-track’ help us, here? Some metaphysicians hold that some potentialities in nature are multi-track; what they mean can be illustrated with an example.
Consider the case of an electron that is electrically charged and is subject to an electrostatic force when placed at some distance from an electric charge, but subject to a different force when at a different distance from another charge (Choi and Fara 2012). The way this case is accounted for, by some at least, in the current power literature, is by positing that ‘being electrically charged’ is a multi-track power, where: ‘multi-track’ powers or dispositions correspond to more than one pair of stimulus conditions and type of manifestation (see e.g. Vetter 2013; Bird 2007; Bird 2005a; Ellis and Lierse 1994; Ryle 1963) by contrast to single-track dispositions, which are picked out by one type of stimulus and one type of manifestation only. But this does not address the research question that drives this project: multi-track accounts simply organise the complex manifestation of certain potentialities into 'tracks', but do not tell us how this complex manifestation derives from the potentiality; a potentiality still remains a ‘black box’. What we need is an account of the internal complexity of potentiality.
Potentialities are instantiated physical properties, which, until now, have been defined in the relevant literature in terms of their manifestations (e.g. electrical attraction is the manifestation of magnetic power; see e.g. Armstrong, Martin and Place 1996; Bird 2007; Lowe 2009; Mumford and Anjum 2011; etc.). The manifestation of a potentiality is the change in the world that the potentiality enables its possessor to bring about or suffer. This (state of the art) definition of what a potentiality is, however, places potentialities ‘in the shadow’ of changes, as ‘mystery’ entities whose presence, in appropriate conditions, brings about the changes. So conceived, potentialities afford a mere ‘all or nothing’ option – that is, the option of positing potentialities tailored to explanations, where and when a potentiality is needed; or of leaving an explanatory gap open. This is precisely what, by the lights of philosophers and scientists alike, raises an important concern: that potentialities, albeit posited to account for how things do what they do (or, fulfil their functions), are used as explanatory ‘black boxes’, with no adequate explanation of how potentialities do the metaphysical work they do.
Potentialities appeal to philosophers and scientists alike when they search of explanatory causes of changes in the natural world; on this, there is broad consensus. But this is only the starting point, for ontology. How do potentialities do what we use them to explain? This project aims to change the current ‘black box’ conception of potentialities, by starting from the opposite direction to the ‘standard’ approach to defining potentialities – from the conditions of their generation rather than of their manifestation. Scientists measure what occurs in nature, to predict what will be. Philosophers examine what there is, to figure out what it is and what it can do. Philosophers do so, by hypothesising how things may be, if they are to be able to do this and that on account of their powers. Herein lies a lacuna that this project will address: we lack some of the necessary concepts to entertain the full range of possibilities of what may be the case at the fundamental level of reality. (The background umbrella-assumption to this claim is Power Ontology: the view that at the basic elements of reality are potentialities, only.) This project aims to formulate the missing concepts: we know how to divide material reality into parts, and recognize its structures; but we have no concepts for dividing dynamic reality into parts, where dynamic reality is the level at which potentialities (capacities, powers, dispositions) are the physical constituents of what there is.
Given the centrality of potentialities in current scientific as well as philosophical thought, to recognize and understand the ontological differences between atomic potentialities and irreducibly complex ones is a game changing move for both domains of investigation. Complex potentialities are found everywhere around us, in the structural essences of biological organisms, in social movements, in periodic natural processes, in artefacts, in elementary systems in nature, between fundamental physical systems in nature (e.g. a magnetic fields) and their emergent systems, and within the cosmic realm(s) of nature. We need new conceptual tools for understanding their dynamic complexity, and for building explanatory accounts of the capacities for the complex behaviour of things.