In a sense this is correct. However note the co-extension of "similarity" and "difference". Trivially any
two "items" are functionally "similar" by virtue of them being both the objects of comparison, but they are also "different" because there are two of them. What matters is the functional basis on which "the list" might be composed, but note that "itemization" already implies an "observer" to establish functional categories.
If you have followed that paradox, it implies that "traditional logic" is useless in solving identity issues because being based on set theory, set membership per se
is beyond logic's jurisdiction.
Note that whatever psychological
issues there are with "self identity", the significant
ones are social
. (Duty, culpability...being in one's right mind...fidelity ...recognition of family ...etc). This point adds weight to the argument that "self" is a social construct. Note too that when social constraints are removed as in dreams, the "self" that operates therein is rarely recognizable.