Dispositions in Nature and Physics

Dispositions in Nature and Physics

by Ian Thompson

In order to advance Theistic Science, we need to discuss several key concepts and ideas concerning nature and physics. Only then can see see how theism and physics form a unified picture. 

These ideas are 

1. that natural objects can have real dispositions, 
   
2. that it is coherent to talk of 'dispositions according to what is actual', 
   
3. that meaning can be given to the term ' derivative disposition'.
   

Explanations therefore start with the meaning of the term 'disposition', and the observation that dispositional properties can never be reduced to entirely static or formal structural properties. Their explanation must always involve some irreducibly 'causal' feature of some kind: some dynamic (rather than static) property.

Dispositions first appear in physics as the macroscopic features of observable objects that we wish to explain. Dispositional properties are largely those which cannot be explained purely by the location and shape of these objects, but require causal kinds of ascriptions and analyses, as explained above, in terms of causal powers. Thus the elasticity of a solid, for example, is explained in terms of the attractions between the electrons and their neighbouring atoms. Note that it is not enough to say that the elasticity can be explained simply in terms of the 'electronic structure', as purely structural properties cannot explain dispositional features without assuming some dispositions (such as charge, mass etc.) inherent in the electrons themselves. This irreducibility of causal explanation in physics has been discussed in detail elsewhere[9]. 

Physics should contain not only a phenomenological description of causes[17], but also a mathematical foundation that determines causes according to actualities. In Newtonian physics 'according to what is actual' means 'according to the spatial shape and configuration of the atomic particles'. In quantum mechanics 'actuality' means 'the quantum numbers of the most elementary particles, and also the definite past events that determine the current quantum state'. 

A distinction is being made between the 'Principal Cause' (that disposition which operates), and the 'Instrumental Cause' (that circumstance by means of which dispositions operate). Principal causes operate according to instrumental causes. Both are necessary for any action, for example, when a stone is let fall: the principal cause is the earth's gravitational attraction, and the instrumental cause is our action of letting go. Its hitting the ground is thus caused by our letting go, but only as an instrumental cause. Many common uses of 'cause' refer to instrumental causes rather than principal causes, as it is only in the instrumental sense that events can be said to be causes. The distinction between principal and instrumental causes will be very important, as thestic science will claim that God is the original principal cause of all events. Principal causes cannot operate without suitable conditions and actual circumstances (i.e. without suitable instrumental causes), and theistic science will want to see that the selection of which principal causes can operate must depend on which instrumental causes are actually present.