688 Commentary : ‘ The child is father of the man . ’ The relationship between child health and adult mortality in the 19 th and 20 th centuries

In the early years of the twentieth century, enormous concern was focused on the relationship between the health of the child and the welfare of the nation. In 1902, Leslie Mackenzie and Matthew Hay informed the Royal Commission on Physical Training (Scotland) that large numbers of children in Aberdeen and Edinburgh were suffering from serious medical conditions which could pose a threat to them in later life, and in 1904 the Interdepartmental Committee on Physical Deterioration devoted more than one-third of its report to conditions affecting the ‘juvenile population’.1 In 1905 Leslie Mackenzie told the Royal Society of Edinburgh that the most important single lesson to emerge from the enquiries was the need to make the individual citizen fit for the environment around them. ‘One truth we have already realised—if we would fit the man for his environment, we must begin with the child. “The child is father of the man.”’2 As this statement indicates, contemporary medical opinion had already begun to emphasize the importance of child health and its relationship to the adult, but it was not until the 1930s that epidemiologists began to devote serious attention to the role which factors operating in early childhood might play in determining the chronological pattern of adult mortality. In 1934, Kermack, McKendrick and McKinlay suggested that if the decline of mortality in England, Scotland, Wales and Sweden in the second half of the nineteenth century was examined in terms of the experience of particular cohorts, then ‘it would seem that the actual calendar year is of relatively little importance in determining ... mortality. What is of importance is year of birth of generation or group of individuals under consideration’. They went on to suggest that the first fifteen years of life were particularly important in shaping the health of the adolescent and the adult, and that ‘if the above hypothesis is correct, it would be implied that the decreased death rates were largely the result of ... improved physique’.3 The aim of this paper is to examine the impact of Kermack, McKendrick and McKinlay’s work on subsequent approaches to the history of health and mortality. The paper begins with an examination of the relationship between infant and child health and adult mortality, and focuses on the history of mortality decline in Sweden and Scotland. The second section seeks to extend Kermack, McKendrick and McKinlay’s work on the history of mortality decline in England and Wales back into the eighteenth century, and also highlights some important differences in the relationship between childhood and adult mortality in the case of men and women. The third section examines the impact of their work on the development of research in the field of anthropometric history. The final section will discuss the implications of this work for our understanding, not only of the causes of mortality decline in the past, but also for the projection of mortality trends in the future.