Review of Mental Causation: A Counterfactual Theory by Thomas Kroedel (Cambridge University Press, 2021)
By Ramy Amin
Thomas Kroedel takes on the task of defending Non-Reductive Physicalism and what he terms Super Nomological Dualism against the problems of interaction and exclusion. He provides a counterfactual theory of mental causation where causation is understood minimally as difference making, and counterfactual dependence of an event p at time t on event m at time t-1 is taken to be sufficient to establish that m is a cause of p. He goes on to sketch robust arguments for both positions to claim causal efficacy of the mental over the physical, thus establishing that all views on the mind-body problem, and not just reductive physicalism, can make intelligible claims of mental causation. On several occasions throughout the book, Kroedel pauses to explain why his theoretical choices are better than the alternatives, hence providing the reader with ample reasons for entertaining the assumptions with which he is working.
There’s no question of Kroedel’s technical mastery in handling counterfactual mazes. Nevertheless, due to space limitation, I will focus in my review on raising a critical point regarding explanatory relevance, which, due to such a minimalist view of causation, becomes a muddled affair. To see how, consider two examples Kroedel gives of what counts as a cause.
The first example is of him bumping into Albert, who goes on to miss his bus and meets his future wife on the next one. They go on to give birth to a child, Berta, who dies 90 years later. Because, on his model, counterfactual dependence is sufficient for causation, Kroedel takes the following two claims to be equivalent: 1) had he not bumped into Albert, Berta wouldn’t have died, and 2) him bumping into Albert caused Berta’s death. He emphasizes that “[t]he appropriate response is to accept that my bumping into Albert does cause Berta’s death and to explain away appearances to the contrary as a pragmatic phenomenon.” (48).
The second example is of someone getting electrocuted as they stand on an aluminum ladder:
being made of aluminium, the ladder is also opaque. Opacity too supervenes on physical properties and can be realized in different ways. The realizers of opacity are closely related to the realizers of conductivity. Almost all conductors are opaque. Some conductors are transparent (see Ginley et al. 2010), but they are not used to make ladders. Thus, it seems that if the ladder had not instantiated any realizer of opacity, I would not have been electrocuted either. It follows from the argument for downward causation that the instance of opacity causes my electrocution. (68).
Kroedel understands that it seems highly implausible that citing himself bumping into someone and opacity as causes of someone dying and another getting electrocuted, respectively, would count as satisfactory explanations. His solution is to emphasize that:
If event e counterfactually depends on an earlier event c, it follows that c is a cause of e. It does not follow that c is among those causes of e that are explanatorily relevant, and hence worth mentioning, in any given context. (48)
Divorcing explanatory from causal relevance produces a tension that Kroedel resists by considering how, on his theory, attempts to deny these conclusions produce unwanted results. Nevertheless, the question remains: if these conclusions stand, what prevents mental causation from operating in similar ways, rendering it explanatorily inept? What we get in terms of identifying conditions for explanatory relevance is that “mental events do typically count as explanatorily relevant” (75). However, if any mental event m can be cited as a cause for a later physical event p only because m falls on the same causal path leading to p and p wouldn’t have happened if m hadn’t happened, then the causal relevance of the mental on the physical is lost, since we can conceive of Albert missing his bus, meeting his wife, and the subsequent death of Berta due to some event other than someone bumping into him. And if mental events stand in an opacity-like relation to physical events, then more is needed to ensure that mental causation doesn’t collapse into epiphenomenalism, since we can conceive of someone being electrocuted had the ladder been conductive yet not opaque. However, discussions of causal relevance and epiphenomenalism are fairly limited in the book. Still, the book is an impressive addition to the literature on philosophy of mind, causation, and counterfactuals.
