EVER SINCE GOMPERTZ

In 1825 British actuary Benjamin Gompertz made a simple but important observation that a law of geometrical progression pervades large porti ons of different tables of mortality for humans. The simple formula he derived describing the exponential rise in death rates between sexual maturity and old age is commonly referred to as the Gompertz equation -a formula that remains a valuable fool in demography and in other sci entific disciplines. Gompertz's observation of a mathematical regulari ty in the life table led him to believe in the presence of a law of mo rtality that explained why common age patterns of death exist. This la w of mortality has captured the attention of scientists for the past 1 70 years because it was the first among what are now several reliable empirical tools for describing the dying-out process of many living or ganisms during a significant portion of their life spans. In this pape r we review the literature on Gompertz's law of mortality and discuss the importance of his observations and insights in light of research o n aging that has taken place since then.