What am I? An instance of the rational nature. This is why I was conceived by parents, grew in a womb, was born of a woman, grew by eating, sensed and learned by it, felt passions, learned by abstraction, knew being, desired vindication, grew up in a society, laughed at jokes, sought friends, feared loss, desired independence, loved my parents, had to seek work, desired fulfillment, was determined by my habits, had some talents and gravitated toward what perfected them, fell in love, got married, conceived a child, desired God, etc. These are the sorts of things that showed me myself most profoundly- and they are nothing other than instances of the rational nature manifesting itself.
There is a certain tendency in modern thought to understand “person” in such a way as to minimize or even explain away the primacy of nature. Such an opinion understands man only superficially; it confuses mere individuation with personality; what is merely unique with what we most fully are. Man’s most profound experiences of his own self are per se in experiences which are common to the whole human race- experiences like the sort mentioned in the first paragraph.