Hylemorphic animalism, brain transplant and ‘brains in a vat’

Animalism, as a theory of diachronic personal identity, asserts that the only necessary criterion for the survival of a human person over time is its connection to the human animal. Opponents of animalism, however, use numerous thought experiments, the most famous of which are the Brain Transplant Case and the Remnant Person Case, to demonstrate that the original thesis of strict animalism, despite all its metaphysical conciseness, cannot be accepted because it contradicts our fundamental psychological intuitions.
A possible solution is offered by an original variation of animalism, based on the hylemorphic metaphysics of form and matter of Aristotle and Thomas Aquinas, – hylemorphic animalism. As a necessary condition for the preservation of the human personality, this view asserts its identity not simply with a biological organism, but with a rational and sentient substance. It examines the basic tenets of hylemorphic animalism regarding diachronic identity, and whether hylemorphic animalism can offer a solution to the brain transplant and remnant person thought experiments that differs from strictly materialistic variants of animalism.
The research concludes that hylemorphic animalism, despite introducing a substance identical to the human person, does not provide a qualitatively different solution to the Brain Transplant Case, but allows for an effective resolution of the Remnant Person Case.

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