One way to achieve immortality is simply not to die. This goal of alchemists and others has been achieved at least once in earth’s history: the oldest known living creature is a bacterium found in the year 2000 in salt crystals near Carlsbad in New Mexico, where it had been buried for two hundred and fifty million years. Placed in nutrient, the bacterium reproduced, and colonies of its scions are happily thriving in laboratories in the US. Assuming all of this to be true, we can surmise that the microscopic organism, or more likely its spore, finding itself in an environment neither hostile nor conducive to reproduction, shut down and waited. Did time pass, or did it not? Are the organisms in those petri-dishes the same as the one who lived at the time that the trilobites became extinct, or are they new beings?