The Mishap of Reichenbach Fall: Singular vs. General Causation

Abstract

[Introduction] What is the relationship between claims of singular causation such as 1. David's smoking caused him to develop lung cancer, and claims of general causation, such as 2. Smoking causes lung cancer? Hume held that the truth of singular causal claims depended upon the existence of universal regularities in nature. In the first Enquiry, for example, Hume wrote that we may define a cause to be an object, followed by another, and where all the objects similar to the first, are followed by objects similar to the second. (Hume [1748] 1955, §VII) Davidson (1980) concurs, while noting that it may not be apparent which generalization is instantiated by any particular episode of singular causation: [l]f 'a caused b' is true, then there are descriptions of a and b such that the result of substituting them for 'a' and 'b' in 'a caused b' is entailed by true premises of the form of (L) and (P) [where (L) provides the form of a causal law, and (P) provides the form of premises describing initial conditions) ... If this is correct, it does not follow that we must be able to dredge up a law if we know a singular casual statement to be true; all that follows is that we know there must be a covering law. (pp. 159-60). Hume and Davidson may be understood as pursuing the following strategy: analyze the truth-conditions of general causal claims in terms of universal regularities in nature, and then treat singular causal claims as describing instantiations of such regularities. Let us call this the Humean strategy.

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