Now I want to write a book about a world where individual humans don't have immortal souls but cities do. Would a person moving to a different city be like someone having a blood transfusion? If dead cities can be reincarnated as other cities, does that mean current-day Istanbul was Constantinople in a past life? Or does reincarnation happen more randomly, and Constantinople just happened to become some random town in New Jersey? Is genocide like murder for cities, or is it more like having a limb amputated?

~~oh shit i've accidentally reinvented hetalia from first principles~~

Yes, in fact, only for higher animals it is possible to draw a clear line between them. For plants (clones) this is less possible.

So considering the life of anything other than an animal, probably there is no clear "I" anywhere else. It is always rather a "we".

This is awsome, thanks!