Russell Standish writes: > On Sun, Oct 08, 2006 at 12:35:44AM +1000, Stathis Papaioannou wrote: > > This is > > literally true, given that from moment to moment, even in the absence of > > teleportation > > etc., the atoms in your body turn over such that after a certain time none > > of the > > matter in your body is the "same", and before this time the fact that some > > of the > > matter in your body is the "same" is accidental and makes no difference to > > your > > conscious experience. > > > > We _really_ need to dispell this myth. It turns out that A bomb tests > prior to the partial test ban treaty provides a unique clock that > allows one to measure when a particular cell was born. It turns out > that whilst this statement is true of various organs (eg the gut in > particular), neurons turn out to have an average age just two years > less than the age of the person (as measured in cadavers), ie most are > born during the rapid brain expansion that occurs during the first two > years of life. > > This is crucial, because I would suspect that neurons have far more > relevance to one's person, than do gut cells. > > I posted on this before - it was reported in a recent New Scientist. I > can dig out the reference if people are interested.
I'd be interested in the reference. However, I wasn't referring to turnover of cells, but to turnover of components of cells. Water and electrolytes are freely and continuously turned over while proteins and other structural components are continuously breaking down and being replaced. I'm not sure of the numbers but I would guess that only a tiny percentage of the matter in a neuron would be the same years later. If there are trillions of radioactive atoms to begin with then by chance some of them will persist in a particular cell provided it does not die. What is actually preserved in a neuron which survives over the course of a person's life is a rough template and physical continuity, not the matter it is comprised of. But for a few lucky atoms, ordinary living is equivalent to destructive teleportation. Stathis Papaiaonnou _________________________________________________________________ Be one of the first to try Windows Live Mail. http://ideas.live.com/programpage.aspx?versionId=5d21c51a-b161-4314-9b0e-4911fb2b2e6d --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Everything List" group. To post to this group, send email to firstname.lastname@example.org To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/everything-list -~----------~----~----~----~------~----~------~--~---