Without memory a person cannot act like the person they consistently seem to be. Our actions are anchored in our past experiences that are in our memory. There is no I, no Sam, that is consistently carried from one moment to next or from childhood to adulthood. There is an idea of Sam that is based on the memories and experiences that I have accumulated over my 30 years. If you take these away there will be no Sam. I could not possibly be me.Without memory I would not have the capacity to act like Sam, not the way that I perceive me to be and not the way that others perceive me to be. Take away memory and the sense of self that we all experience ceases to exist. There will be no more you.
If you take two people and were somehow able to completely switch their memories without changing their biology they would become the person whose memories now occupy their mind. In no way would they somehow remain “themselves” with the new memories of another person. They would be that person whose memories they now have. Memory is what makes us “ourselves” and it influences what actions we will take in the future. If we take these same two people who both have completely different memories and were able to inject one new and identical memory into both their brains then they would react to that memory differently despite the memory that was injected being identical. The memory could be an altercation at a specific pub and to person A and person B they remember the experience exactly the same. But what changes in their thinking and what actions they decide to take will be determined by the whole collection of past experiences that they do not share. Person A decides an altercation like this is so rare, and because they consider themselves a peaceful person, they will continue to visit this pub and think no more about it. However, person B decides that this was a rather traumatic experience and will be far more vigilant with strangers in the future and they have decided not to return to that same pub ever again so they don’t risk the same altercation. There is an infinite amount of possibilities and outcomes of such an event and all of these outcomes are determined by our personal memories and experiences.
If memory determines who we are, who we think we are and who others think we are and taking away memory takes away these things then who are we? Without memory how can you be you? Without memory what are you?
“…there is an idea of a Patrick Bateman, some kind of abstraction, but there is no real me, only an entity, something illusory, and though I can hide my cold gaze and you can shake my hand and feel flesh gripping yours and maybe you can even sense our lifestyles are probably comparable: I simply am not there. It is hard for me to make sense on any given level. Myself is fabricated, an aberration. I am a non-contingent human being.” – Patrick Bateman, American Psycho.
Companion audio: https://youtu.be/ZfNXCkNjX1Y