Upward Causation

When the direction of causal influence extends from 'higher' levels of reality (say, those above the level of physics) down to 'lower' levels of reality, we speak of downward causation. The various sciences are commonly, though not uncontroversially, assumed to stand in some hierarchical relationship to each other. Physics is considered the basic science, with the other sciences (chemistry, biology, psychology, and the social sciences) stacked on top, each dealing with mereologically more complicated fusions of physical events than its predecessor. This assumption is often complemented with the principle of the causal closure of the physical realm. This principle states, in effect, that physical events (even huge conglomerates of physical events possibly constituting such macro-events as earthquakes, mental states, or a crash in the stock market) are causally produced by antecedent physical events alone (though these latter events may in their turn be more illuminatingly describable in the jargon of relevant nonphysical sciences). That is to say, fundamentally there is only one kind of "real" causation, namely, causation at the level of microphysical events. Thus, causation extends upward all the way from the physical domain to the higher-level domains supposedly stacked up on top.

Consequently, according to this view, causation at these higher levels of existence, in particular mental causation, is always in some sense derivative or epiphenomenal. Jaegwon Kim's doctrine of supervenient causation, for example, holds that there exists a macro-causal relation between two events just in case there is a micro-causal relation between the two events upon which they supervene. Clearly such a definition of supervenient causation renders all macro-causation epiphenomenal. In particular, since mental causation is a species of macro-causation, the way the mind matters in this world is, on this view, epiphenomenal as well. It has been observed, however, that Kim's doctrine presupposes an unnecessarily restricted notion of event-supervenience known as local supervenience.

See also Causation; Downward Causation; Supervenience

Bibliography

kim, jaegwon. "epiphenomenal and supervenient causation." midwest studies in philosophy 9 (1984): 257–270.

theo c. meyering