Start with a whole human being. Someone you know well, a friend, parent, spouse, cousin, uncle, yourself even, it doesn’t really matter as long as you know that individual well enough that you can, with some confidence, describe them in extensive detail. Now, who are they? what are they? Where do they begin and end? Every one of those probably smacks of bullshit trickster philosophy and you’d be justifiably right if that is how you choose to respond, but humor me for a moment.
So you’ve got your person in mind. Think about them, what makes them them, the person you know or have known, imagine them whole, and now imagine that they’ve lost an index finger. No, this is not some kind of thought exercise in the sadism of interrogation or violence of combat, just imagine that one day this person woke up and the finger was gone, painlessly, bloodlessly, vanished.
I would assume that you still consider this to be the same individual, despite the minor loss of a pointer.
But the next day an arm disappears, same as the finger, no pain no blood no warning, just gone into the ether. Probably still the same person, maybe? But the next morning a synapse in their brain does a disappearing act, and the morning after that a small part of the frontal lobe makes its own break.
Are we a collection of atoms, by virtue of whose unique arrangement we derive an identity, manifest ourselves’? I think that is a clearly disproven hypothesis. Are we then our brains or emotions or some kind of matrix of nerve and muscle? I don’t put much faith in that either, people have lost nearly entire hemispheres of their brain removed or rendered a cognitive wasteland yet have continued to function and interact in a fashion nearly or completely identical to their pre-disaster selves.
So perhaps identity, what makes me me and you you is a percentage of some kind. If I started shutting down muscle, bone, and neuron function in my own body there would be a threshold at some point where ‘I’ that annoyingly common pronoun would cease to be. But again, here, this idea that what defines our individual identities is some form of magical ratio between original self and current self is fairly nonsensical. I was a little over 7 pounds when I was born and weigh over 200 now, there is a lot of extra me thats been accumulating since birth.
The easy and obvious answer is that we are never the same person, that just like time, each moment means a different individual, a person transmuted imperceptibly into somebody else, discovering only after the aggregation of uncounted and unnoticed minute alterations that they are indeed different. But I think thats a bullshit answer too in some ways. If we’re all changing all the time at near constant rate then the relative effect is nothing. That is a generalization never intended to describe all situations, but regardless,’constant change’ pretty much renders itself irrelevant.
I like to think that we, in the collective, all of us, are defined not self-objectively, but by the interaction of our self conceived identities with those of others. I perceive you, you perceive me, we all spin a giant tapestry of preconceptions based on experience or extrapolated from experience that aids our passage across this mortal coil, and somewhere betwixt the two (or three?) our identity lives. It’s a proven, irrefutable fact of life that human beings subjected to extreme isolation quickly collapse into violent insanity. We have to have others, the action/reaction/counterreaction framework of human to human contact, even with all its supposition and inaccuracy and misunderstanding to even begin to have a clue who we, I, you, us is. I would not exist without the affirmation of another human that I in fact did exist. So we are all an indeterminate blend of what we imagine ourselves to be and what everyone else imagines us to be, my notions of self informed by the way I perceive others perceive me, their idea of who I am informed by perceptions of how I perceive them perceiving me.