How much of my identity is up to me? Some of it — I can decide to be a Jehovah’s witness, or a democrat, or a vegetarian, or a fan of Styx. Unlike in the past when many of these affiliations were handed to me by the circumstances of my birth, now many aspects of my identity are up to me. I am self-defining.
But not entirely so. Some aspects of my identity are decided by other people. Consider my identity as Uncle Eric. When my brother Flippy had his first child he turned me into an uncle. I did not get a say in the matter.
My children are not married, but if they do I will acquire another identity, one which has a name in Yiddish but not in English. This is the identity of machituneh.
Definition: A is a machituneh of B iff A has a child married to a child of B.
This identity is also not up to me. My children can make me a machituneh of somebody else whatever I say, just as my brother can make me an uncle, like it or not.
I can decide to be a vegetarian but I cannot decide whether or not to have the identity of machituneh to a meat-eater. I can identify as Episcopalian but I cannot decide whether or not to be machituneh to a Jew.
I foresee and look forward to an era of universal machitunimification. We can argue about whether or not we are literally brothers or siblings, but once everyone has descendants married to everybody else’s descendants we will be a single human family.
Some day maybe humans and intelligent bears will produce bear-man offspring and humans and bears will be machitunim. I suppose that the incorporation of the first mitochondrion and chloroplast by the first eukaryotic cell made eukaryotes and prokaryotes into machitunim.
But that happened a long time ago– people forget to invite prokaryotes to Thanksgiving.