An Euler contribution to stable theory from Süssmilch's göttliche Ordnung

In a paper published in 1760, the great Swiss mathematician Leonard Euler developed relationships between age structure and vital rates that would hold for stable populations, but without attention to the process by which stabilization comes about. He had not overlooked the latter problem. We introduce in this paper an earlier brief communication of his to Johann Peter Süssmilch in which he postulates that stability must ultimately result if fertility and mortality regimes are fixed. The mathematical treatment of this concept had not been thought to predate Alfred Lotka's work in the early part of the present century.