Causality

Another central platitude of the concept of causality may be called the recipe platitude: causes are recipes for producing or preventing their effects. This platitude is normally cast in terms of manipulability: causes can be manipulated to bring about certain effects. G. H. von Wright (1906–2003) developed this thought into a full-blown theory of causality. He took it that what confers on a sequence of events the character of causal connection is "the possibility of subjecting cause-factors to experimental test by interfering with the 'natural' course of events" (1993, p. 117). Since manipulation is a distinctively human action, he concluded that the causal relation is dependent upon the concept of human action. But his views were taken to be too anthropomorphic. For, do we not think that there would be causal relations, even if there would not be any humans around capable of manipulating anything? Yet, recently, there have been important attempts to give a more objective gloss to the idea of manipulation. James Woodward (2003) introduces a notion of intervention that is not restricted to human action and argues that a relationship among some magnitudes X and Y is causal if, were one to intervene to change the value of X appropriately, the relationship between X and Y would remain invariant but the value of Y would change, as a result of the intervention on X. This interventionist account has been developed by Judea Pearl (2001) into a rather powerful mathematical tool, known as Bayesian probabilistic networks, for discovering and establishing causal relations from relations of probabilistic dependence among variables. An attraction of the interventionist approach is that it is not so much concerned with the metaphysics of causality as with the epistemological and methodological circumstances under which causal facts can be ascertained.