[en] The triune concepts of aging, toxicity, and longevity hormesis are best integrated through analysis of mortality kinetic data. As a means of investigating the usefulness of Gompertz analysis in the characterization of mammalian aging, toxicity, and longetivity hormesis, a series of hypotheses is posited and discussed. This is followed by an in-depth discussion of longevity hormesis, including a survey and evaluation of the database. In summary, in animal populations, a phenomenon of unknown mechanism, termed longevity hormesis, has been demonstrated to reversibly reduce instantaneous mortality rates, termed Gompertzians, to values below those of control populations. Presumably, this is mediated through a temporarily lessening in one or more types of injury, and this is initiated by exposure of organisms to a variety of different stimuli including chemical and radiation exposures. This response of Gompertzians is distinctly different from that achieved through caloric restriction. Exposures of populations of eutherian mammals to external stimuli, in addition to enhancing life span through longevity hormesis and/or caloric restriction, can also decrease longevity by causing either reversible or irreversible toxicity. Analyses of several data sets suggest that all these actions superimpose their injury promoting or decreasing effects on the hitherto state of the organism. Evidence for the existence of longevity hormesis in humans is fragmentary and controversial at best