Horst, S. (2009). Naturalisms in Philosophy of Mind. Philosophy Compass, 4(1), 219-254.
[Abstract]Most contemporary philosophers of mind claim to be in search of a ‘naturalistic’ theory. However, when we look more closely, we find that there are a number of different and even conflicting ideas of what would count as a ‘naturalization’ of the mind. This article attempts to show what various naturalistic philosophies of mind have in common, and also how they differ from one another. Additionally, it explores the differences between naturalistic philosophies of mind and naturalisms found in ethics, epistemology, and philosophy of science. Section 1 introduces a distinction between two types of project that have been styled ‘naturalistic’, which I call philosophical naturalism and empirical naturalism. Sections 2 to 6 canvass different strands of philosophical naturalism concerning the mind, followed by a much briefer discussion of attempts to provide empirical naturalizations of the mind in Section 7. Section 8 concludes the essay with a consideration of the relations between philosophical and empirical naturalism in philosophy of mind, arguing that at least some types of philosophical naturalism are incompatible with empirical naturalism.
[Citing Place (1956)]  
Citing Place (1956) in context (citations start with an asterisk *):
4. Reductive Philosophical Naturalism
4.1. Analytic Behaviorism and Type Identity
* Type-identity theory is the thesis that that each legitimate mentalistic kind (e.g., pain) is identical to some (possibly complex) physical kind (e.g., C-fiber firings) (Place; Smart). This view was quite influential in the 1960s and 70s, but is now largely rejected by philosophers of mind. The main reason for its rejection was the growing popularity of functionalist accounts of mental state types in the 1970s and 80s. According to such accounts, mentalistic kinds, like ‘pain’ or ‘belief ’, are typified functionally, much like biological kinds such ‘heart’ and kinds of computational circuits like ‘AND-gate’. Functional kinds are distinguished by what they do, rather than by how they do it, or by their structure. But functional kinds can be realized in multiple ways: human hearts and earthworm hearts bear few structural similarities, and circuits and programs with the same functional form can be implemented in computers that have little in common physically. So if mental kinds are functional kinds, they are multiply realizable – humans, earthworms, Martians, and androids might have the same functional states, but these would be implemented differently in each case. The relation between mental and physical kinds is thus not one-to-one, as held by type-identity reductionists of the 60s, but one-to-many.