Abstract
The animalist view of personal identity, according to which we human persons are identical to animals, is arguably the simplest view of the relationship between human persons and animals. But animalism faces a serious challenge from the possibility of brain transplants. This chapter develops, on behalf of animalism, a new way of modeling such cases. The model is developed by analogy with situations of environmentally determined reference shift familiar from the literature on externalism in the philosophy of mind and language. The resulting externalist animalist model is put to work in describing a range of variant cases and in accounting for certain anti-animalist intuitions. In the final section some wider consequences are elucidated, concerning the extrinsic nature of thought, and the coherence, within a broadly materialist framework, of disembodied consciousness.