The topic of longevity was bought up today during the aisle chit-chat session. What will you do if you can live a thousand years. One of the colleagues said he would like to build a self sufficient floating city, which is kinda like the Freedom Ship in the Discovery Channel show. I say I would like to be a historian and antique trader, provided that I’m the one of the few people can live this long. There would definitely population problem if everyone can live long. However longevity doesn’t imply immortal. In a long run the death rate is still 100%, thanks to accident and murders. To make longevity viable, all we need find the equilibrium among birth rate, death rate and resources growth rate.