Presumably all archaeologists know that radiocarbon dates are estimates of true dates, or, more precisely, that they are derived from estimates of the true rate of emission of electrons from radioactive carbon. If it were possible to keep each specimen in the counter for an indefinitely long period or if the emissions occurred with the regularity of clock ticks, there would be no need to talk of estimates of rates. Unfortunately, the emissions do not occur at regular intervals nor is it practical to count for a very long time, so there is no escape from the uncertainty of estimation.