Abstract

Externalist theories of thought content are sometimes arrived at by reflection upon Twin Earth thought experiments of the sort made famous by Hilary Putnam and Tyler Burge. The conclusion many philosophers draw from these thought experiments is that certain types of thought contents are individuated, in part, by environmental or socioenvironmental factors. This doctrine of "Twin Earth content-externalism" implies that it is possible for thinkers that are alike in all intrinsic physical respects to differ in the contents of their thoughts by virtue of differences in their environments.