Paul Henne

Any theory of mind needs to explain mental causation. Kim’s exclusion argument concludes that non-reductive physicalism cannot meet this challenge. One classic reply is that mental properties capture the causally relevant level of generality, because they are insensitive to physical realization. However, this reply suggests downward exclusion, contrary to physicalism’s assumption of closure. This paper shows how non-reductive physicalists can solve this problem by introducing a contrastive account of causation with non-exhaustive contrasts. That view has independent justification, because it is also needed to solve other puzzles. On this theory, both a mental property and its physical realizer can cause the same physical effect without lapsing into any problematic overdetermination when they cause that effect in contrast with distinct foils. This contrastive solution has advantages over previous accounts of mental causation and is defended against objections.

A standard principle in ethics is that moral obligation entails ability, or that “ought implies can”. A strong case has been made that this principle is not well motivated in moral psychology. This paper presents an analogous case against the theoretical motivation for the principle. The principle is in tension with several foundational areas of ethical theorizing, including research on apologies, excuses, promises, moral dilemmas, moral language, disability, and moral agency. Across each of these areas, accepting the principle that obligation entails ability creates a theoretical problem that is more easily solved by rejecting it rather than accepting it. I conclude that the motivation for the principle is weak and that “ought implies can” should be rejected in ethics on theoretical grounds.

How do scientific explanations for beliefs affect people's confidence that those beliefs are true? For example, do people think neuroscience-based explanations for belief in God support or challenge God's existence? In five experiments, we find that people tend to think explanations for beliefs corroborate those beliefs if the explanations invoke normally-functioning mechanisms, but not if they invoke abnormal functioning (where “normality” is a matter of proper functioning). This emerges across a variety of kinds of scientific explanations and beliefs (religious, moral, and scientific). We also find evidence that these effects can interact with people's prior beliefs to produce motivated judgments.

Existing research suggests that people's judgments of actual causation can be influenced by the degree to which they regard certain events as normal. We develop an explanation for this phenomenon that draws on standard tools from the literature on graphical causal models and, in particular, on the idea of probabilistic sampling. Using these tools, we propose a new measure of actual causal strength. This measure accurately captures three effects of normality on causal judgment that have been observed in existing studies. More importantly, the measure predicts a new effect ("abnormal deflation"). Two studies show that people's judgments do, in fact, show this new effect. Taken together, the patterns of people's causal judgments thereby provide support for the proposed explanation.