Singular and General Causal Relations : A Mechanist Perspective

1. Singular and General Causal Relations: A Mechanist Perspective Stuart Glennan Butler University

2. The singularist and generalist view of causation • The generalist view: Particular events are causally related because they fall under general laws • The singularist view: Causal relations obtain between particular entities, and causal generalizations are true, to the extent they are true, in virtue of generalizing over singular causal facts.

3. Talk Outline • Productivity, Relevance and Singularism • The grounds of the Singularist Intuition • Three “mechanistic “theories • Process theories • Mechanical theories • Manipulability theories • The character of fundamental interactions and the case for singularism

4. Productivity & Relevance • Sober, Elliott. 1984. Two concepts of cause. PSA: Proceedings of the Biennial Meeting of the Philosophy of Science Association • Hall, Ned. 2004. Two concepts of causation. In Causation and counterfactuals. • Godfrey-Smith, Peter. 2010. Causal pluralism. In Oxford handbook of causation • Glennan, Stuart. forthcoming. Mechanisms, causes and the layered model of the world. Philosophy and Phenomenological Research.

5. Productivity and Relevance • Sometimes we have production without relevance (difference making): e.g. – overdetermination cases like firing squads • Sometimes we have relevance without production: e.g., omissions like the failure to break at a stop light. • Generalist or type level causal theories focus on relevance, while singularist theories focus on production – but there are exceptions

6. The Singularist Intuition • The Nature and Observability of the Causal Relationship C.J. Ducasse, 1926 • Causality and Determination Elizabeth Anscombe, 1971

7. The Singularist Intuition … [T]he cause of a particular event [is defined] in terms of but a single occurrence of it, and thus in no way involves the supposition that it, or one like it, ever has occurred before or ever will again. … And recurrence becomes related at all to causation only when a law is considered which happens to be a generalization of facts themselves individually causal to begin with. Ducasse 1926

8. The Singularist Intuition Causality consists in the derivedness of an effect from its causes . This is the core, the common feature, of causality in its various kinds. Effects derive from, arise out of, come of, their causes. … Now analysis in terms of necessity or universality does not tell us of this derivedness of the effect; rather it forgets about that. Anscombe 1971

9. Three Theories of Causality • Process Theories • Wesley Salmon, Phil Dowe • Manipulability Theories • Jim Woodward, Judea Pearl, also Spirtes, Glymour and Scheines • Mechanical Theories • Glennan, MDC, Bechtel

10. Process Theories • Causal processes are understood as world-lines of objects that propagate causal influence through space-time. • When causal processes intersect they may interact, changing the properties of each process. • Causally related events must be connected by a continuous network of intersecting causal processes. • Process theories are clearly singularist

11. Problems for Process Theories • Process theories provide an analysis of productivity, but have problems with relevance, including: • Irrelevant interactions • Relevant negative causes (omissions, preventions) • Reductive character of analysis of interactions

12. Mechanical Theories • Mechanisms are systems consisting of a set of parts, entities, components. • Activities of and interactions between parts of mechanisms are regular -- characterized by counterfactuallyinvariant generalizations • Mechanisms are hierarchical in the sense that the parts of mechanisms may themselves be parts

13. Advantages of Mechanical Theories over Process Theories • Mechanical theories seem to address the causal relevance problem, in part because of their reliance on counterfactual-supporting generalizations in describing relations between parts. • Because mechanical theories are hierarchical, they seem better suited than process theories to handle the fact that higher level properties are often the causally relevant ones.

14. Manipulability Theories • Causal relations are represented by directed acyclic graphs. Direct Causal Relations between nodes are characterized by functional relations • If X causes Y then an intervention on X will cause a change in Y in accordance with these functional relations.

15. A Mechanism

16. DAG for a toilet

17. The character of fundamental interactions and the case for singularism

18. Some important points about generalizations, counterfactuals and mechanisms: • Interactions between parts of mechanisms “can be characterized by direct, invariant, change-relating generalizations” (Glennan 2002) • These generalizations support counterfactuals. • Outside of fundamental physics, these generalizations are mechanically explicable, meaning that the truth makers for these generalizations are further mechanisms • But eventually we bottom out and have to wonder what the truth maker of the generalization is.

19. A Quick apology to modern physics • This picture of mechanisms presupposes a “classical” view of the fundamental physical entities and interactions • Entities must have definite properties and must be distinct from other entities. Interactions must in some sense be local. • Quantum mechanics tells us this is wrong • Somehow classical entities and properties emerge at some level of organization, and this is our “fundamental” level.

20. Psillos’ asymmetry thesis: • Because of this, Psillos (2004) argues that there is a certain asymmetry between counterfactual and mechanistic approaches • Counterfactuals are needed to underwrite fundamental interactions between mechanisms, but mechanisms can’t always be the truth-makers for counterfactuals. • A genuine case for the priority of counterfactuals over mechanisms would require us to have a reductive account of the truth makers for counterfactuals, but we (or Woodward at least) doesn’t have that.

21. Our key question What in the hell does it mean that, an interaction between fundamental parts of a mechanism “can be characterized by change relating generalization”?

22. Fundamental Interactions Humean Lawlessness The interaction is nothing more than an instance of a pattern that is described by a generalization Nomological Determination The interaction is governed by the generalization (law) Singular Determination The interaction is a singular case of causal determination and any generalizations describing interactions are true in virtue of there being a general pattern of such singular instances.

23. Taking the Positivist Route • One option here is to simply reject the question of which interpretation is right, since it is empirically undecidable. • This is mechanisms sans metaphysics, which is good if metaphysics is nonsense.

24. Against Humean Lawlessness • Humean lawlessness is antirealist about laws and causes. • There are no genuine modal relationships. • Singular counterfactual claims are not really claims about what would have happened in a single case. • Manipulation, like other forms of causing, is a fiction. • The view is, as Mumford claims, “irrefutable, but neither compelling, appealing, nor intuitive.”

25. Against Nomological Determination • The main argument for the nomological determination view is that it explains why there are fundamental level regularities. • The singularist responds that the fact that an interaction at one place is productive should not depend upon what happens elsewhere. • It does not follow from the fact that we live in a world in which fundamental interactions fall under patterns that it is in virtue of these patterns that the productive relationship holds. • We could live in a higgledy-piggledy world

26. For singular determination • The singularist view of determination that is consistent between the fundamental and higher-levels. • Laws are typically understood to be relations that hold in virtue of the properties of the things related. • But the properties of complex things are not basic facts about those things, but are mechanically explicable. Higher level properties and laws depend upon particulars • Consequently, it would be good if the same held at the fundamental level.