Research Group
in Analytic Philosophy

Abstract

When do objects at different times compose a further object?  This is the question of diachronic composition.  The universalist answers ‘always'.  Others argue for restrictions on diachronic composition: composition occurs only when certain conditions are met.  Recently some philosophers have argued that restrictions on diachronic compositions are motivated by our best physical theories.  In Persistence and Spacetime and elsewhere, Yuri Balashov argues that diachronic compositions are restricted in terms of causal connections between object stages.  In a recent paper, Nick Effingham (2011) argues that the standard objections to views that endorse restrictions on composition do not apply to a view that restricts composition according to compliance with the laws of nature.  On the face of it, such restrictions on diachronic composition preserve our common sense ontology while eliminating from it scientifically revisionary objects that travel faster than the speed of light.  
    I argue that these attempts to restrict diachronic composition by appealing to either causal or nomological constraints face insurmountable difficulties.  I argue that neither approach succeeds in preserving our common sense ontology.  I also argue that both approaches face difficulties when considering composition within the context of special relativity