From extended minds to extended persons

The Extended Mind Thesis (EM) claims that cognitive processes can extend beyond the body into the environment. While EM has often been taken to support the Extended Self Thesis, its implications for personhood, personal identity, and personal composition have rarely been explored in a systematic way. This paper aims to fill the gap by connecting EM with the rich metaphysical debate on personhood. We adopt a Lockean framework and distinguish two versions of the Extended Person Thesis: a Weak version (WEP), according to which personhood-defining properties can be externally instantiated, and a Strong version (SEP), according to which persons themselves may be partly constituted by non-biological parts. While WEP follows naturally from EM, SEP requires more substantial ontological commitments. We argue that these commitments, though not entailed by EM, are consistent with its functionalist assumptions. If one is prepared to accept them, as a supporter of EM arguably should, then EM does imply SEP.