Your friendly enquiry about the age of the celebrant elicits the reply that she is celebrating her ("t""p" = ) 50th birthday. According to Gott, you can predict with 95% confidence that the woman will survive between = 1.28 years and 39[×50 = 1,950 years into the future. Since the wide range encompasses reasonable expectations regarding the woman's survival, it might not seem so bad, till one realizes that rule predicts that with probability 1/2 the woman will survive beyond 100 years old and with probability 1/3 beyond 150. Few of us would want to bet on the woman's survival using Gott's rule. "(See Caves' online paper below.)"