This article is only available in the PDF format. Download the PDF to view the article, as well as its associated figures and tables.
The author describes the curve of life as made up of three periods: an ascending portion corresponding to the period of growth; a plateau of from 15 to 20 years representing maturity, and finally, a descending curve corresponding to retrogression and terminating in senescence. The biologic purpose of life is reproduction, "a potential immortality of its kind." Senescence begins at 60 with evidence of body changes, but frequently without deterioration of the mental faculties. The only escape from senility is death from disease. Rejuvenescence is impossible. The increase in the span of life only increases the number of persons who reach this undesirable state. With this gloomy aspect, the reader looks forward with anticipation to the last chapter which deals with old age, the miseries and the methods of making the most of an undesirable condition. To those who reach this period with retained mental faculties added to the ripe