Properties
When entities interact, it is their properties that affect and/or are affected in the interaction. Certain properties of an entity interact with the properties of another entity, producing changes in that entity.
Entities are material objects with properties, and causality operates around properties. Glennan (2002, 344) provides a clear explanation of the nature of the interaction between entities: ‘an interaction is an occasion on which a change in a property of one part brings about a change in a property of another part'.[144] [145] And this is what ‘causation' means.In an interaction, the properties of one entity act on the properties of another entity, producing changes (in other words, effects) in this property. If, for example, a particular property—postcapillary vasodilation—of a chemical entity (nitroglycerine), produces a change in a particular property of an organic entity—relaxation of the arterioles anda decrease in vascular resistance and arterial pressure—with which it has interacted, we are looking at a causal mechanism that has produced an effect. Vasodilation occurs because the properties of nitroglycerine interact with the properties of cardiovascular system and thus produces relaxation of the peripheral arteries and veins, decreasing cardiac output and reducing oxygen demand by the heart muscle. Not all properties are causally relevant; causal relevance distinguishes the properties that produce certain effects from the properties that do not have that 14
power.
Finally, dispositional properties are not independent. They are not dispositions simple, and separate, they are relational properties; in other words, their identity or essence is determined by their relations with other properties, rather than intrinsically. The relational nature of properties is accepted by non-essentialist new dis- positionalists like Mumford (2009), but also by essentialists like Bird (2007), and by those who take one position or the other depending on the properties involved, like Chakravartty (2008). Thus Bird affirms‘According to dispositional essentialism the essence of such a property is determined by its relations to other properties’ rather than purely intrinsically (Bird 2007, 524, 527).
For non-essentialists, it is the identity of the property that is established relationally. Mumford (2004, 95) emphasizes that, ‘there is nothing at all more to’ a property than ‘its relations with other properties’. And as Bird writes (2007, 533), ‘For the dispositional monist, identity of properties is dependent on something else, rather than being primitive (the latter view is quidditism). The something else is the pattern of manifestation relations’.The relational nature of dispositional properties raises the regression or circularity problem. Insofar as the identity of each property is relational rather than fixed, regression is clearly present. New dispositionalists respond to this objection by arguing that more than regression, there is circularity, an acceptable circularity we must learn to work with. As Mumford (2009, 101) argues‘The circle is not too tight. It is big enough for us to grasp an adequate-enough understanding of what our original property is’. Simply put, dispositionalism entails interrelated properties and its nature and identity is determined by that.
Properties are relational, and they cause or are causally affected. In order to account for the production of effects by properties, let’s take our analysis one step further and look at another factor, that of ‘dispositions’ or ‘powers’.
5