Some non-reductionists claim that so-called 'exclusion arguments' against their position rely on a notion of causal sufficiency that is particularly problematic. I argue that such concerns about the role of causal sufficiency in exclusion arguments are relatively superficial since exclusionists can address them by reformulating exclusion arguments in terms of physical sufficiency. The resulting exclusion arguments still face familiar problems, but these are not related to the choice between causal sufficiency and physical sufficiency. The upshot is that objections to the notion of causal sufficiency can be answered in a straightforward fashion and that such objections therefore do not pose a serious threat to exclusion arguments. Keywords Exclusion argument • Causal exclusion • Causal sufficiency • Non-reductionism • Causation • Philosophy of mind • Mental causation • Reductionism 2 Non-reductionists vs. causal sufficiency Non-reductionists about the mind share one commitment. Namely that mental phenomena are distinct from physical phenomena in the following sense: no mental phenomenon is identical to a physical phenomenon. 2 Causal exclusion arguments against such non-reductionism have many formulations. We can take the following formulation, loosely based on Bennett (2008), as a starting point: Mental Causation Mental phenomena systematically cause physical phenomena. Non-Reductionism Mental phenomena are distinct from physical phenomena. Causal Closure Every physical phenomenon has a sufficient physical cause at any given time t (if it has a cause at all at t). Physical Parts For any two phenomena A and B, if A is a physical phenomenon and B is a part of A, then B is a physical phenomenon as well. 3 Causal Exclusion For any three phenomena A, B and C: if A occurs at t and is a sufficient cause for B's occurrence at t + x, no phenomenon C occurring at t that is distinct from A and is distinct from all of A's parts is a cause of B, unless it is a case of genuine overdetermination. 4 Non-Overdetermination There is no systematic genuine overdetermination of physical effects with mental causes. Mental Causation and Non-Reductionism together entail that physical phenomena are systematically caused by phenomena that are distinct from physical phenomena.