Body parts or bodies as spimes or kirkyans... I'm thinking about what life might be like in a far-flung transhumanist future.
We wouldn't have bodies. Not even "foglet" clouds of nanites. We wouldn't have anything material at all, so much as we might sometimes use matter. "Bodies" would be spimes (or kirkyans if you like), which we would fabricate as needed on the fly, update as we use, then drop away like a dead carapice to be recycled (or reused, more likely).
Our kirkyan "bodies" would only be limited by licensing rights to access the matter we need -- like a login name and password gets you access to millions of files in a database, we might "subscribe" to bodies on a time-share type agreement with other users.
This stuff treads heavily into Actor-Network Theory territory, and transhumanism owes alot to ANT if you ask me, whether it knows it or not. ANT holds that all objects we encounter or use have a social aspect that in turn alters our original social world -- that all "objects" are social mediators and social actors. In this way, our technological world (and our natural world) are not seperate from any human social or psychological worlds -- it's a single field of activity, a network of social actors. A human doesn't have to have more prominence than a doorknob in the network, because the importance of a node in the network is determined by the number of social interactions or relationships that node has. I reckon cows fit in too, somehow.
In a library, every book is a social actor, and every book's user is a social actor. But in a spimey/kirkyan world where amaterial (wholly informational?) human actors can up- and download into blobs or fogs of matter at will, books (if they still exist in any meaningful way) become kinda like neural nets that hold memories. We'll go to (or become) "books" to access the information we need... and that's where this gets distinctly kirkyan, because the act of negotiating with the information "object" alters the "one" who does the negotiating. In this kind of world, we don't just read anymore -- where a person is information, "reading" re-writes a person.
As the nanoseconds tick away, we will see that identity is never static.