Most people believe in free will. Whether this belief is warranted or not, free will beliefs
(FWB) are foundational for many legal systems and reducing FWB has effects on behavior
from the motor to the social level. This raises the important question as to which specific
FWB people hold. There are many different ways to conceptualize free will, and some might
see physical determinism as a threat that might reduce FWB, while others might not. Here,
we investigate lay FWB in a large, representative, replicated online survey study in the US
and Singapore (n = 1800), assessing differences in FWB with unprecedented depth within
and between cultures. Specifically, we assess the relation of FWB, as measured using the
Free Will Inventory, to determinism, dualism and related concepts like libertarianism and
compatibilism. We find that libertarian, compatibilist, and dualist, intuitions were related to
FWB, but that these intuitions were often logically inconsistent. Importantly, direct comparisons
suggest that dualism was more predictive of FWB than other intuitions. Thus, believing
in free will goes hand-in-hand with a belief in a non-physical mind. Highlighting the importance
of dualism for FWB impacts academic debates on free will, which currently largely
focus on its relation to determinism. Our findings also shed light on how recent (neuro)scientific
findings might impact FWB. Demonstrating physical determinism in the brain need not
have a strong impact on FWB, due to a wide-spread belief in dualism