Scientific life should be measured in seven year units
Bruce G. Charlton
Medical Hypotheses; 66: 1051-1052
Traditional wisdom and empirical observation unite in recommending a 7 year unit for measuring human life – including individual and institutional science. But, because of astronomy and the decimal system, things tend to be measured either in years, five years or in decades. A year is too short while a decade is too long to measure the trends and transitions of individual or institutional life. And the half decade, such as the ‘five year plan’ beloved by politicians and bureaucrats seems too short. Therefore, seven years should become the standard unit for tracking trends and measuring attainment. Precedents for using a seven year unit include the notorious Jesuit saying: ‘Give me the child until he is seven, and I will show you the man’; and the ‘ninth commandment’ of Leo Szilard: ‘Do your work for six years; but in the seventh, go into solitude or among strangers, so that the memory of your friends does not prevent you from being what you have become’. In a scientific career, seven years is approximately the time spent at high school, the time taken for a traditional basic scientific training of first degree and doctorate, and the period after the doctorate building the knowledge to become an expert specialist. There seems to be enough anecdotal evidence to support the idea that we should reconsider the universal but un-reflective use of decimal units in planning and evaluation. For instance, seven year fellowships and program grants might replace the current five year versions. A new – and previously unconsidered – field of research beckons.
Ten Commandments by Leo Szilard, c1940: Number nine: Do your work for six years; but in the seventh, go into solitude or among strangers, so that the memory of your friends does not prevent you from being what you have become. 
Because of astronomy and the decimal system, human life tends to be measured either in years or decades. Yet, a year seems too short to measure the trends and transitions of an individual life or the life of a human institution; while a decade seems too long. But the half decade, which is often used in politics and by state bureaucracies – e.g., the five year plan, five yearly evaluations of organizations, or five year grants for individual scientists or programs for funding advanced research – seems too short.
I would suggest that traditional wisdom and empirical observation unite in recommending a 7 year unit for measuring human life; and that seven years should become the standard unit for tracking social trends, measuring individual attainment, and for strategic planning and support.
There are precedents for using a seven year unit. These range from the jokey ‘seven year itch’ (after which married men supposedly want to become unfaithful to their wives) to a notorious saying attributed to the Jesuits: ‘Give me the child until he is seven, and I will show you the man’. This led to a famous and very popular UK documentary television series called ‘Seven up’ in which director Michael Apted interviewed a cohort of seven year old children in 1964 and has followed them at seven year intervals ever since. Most viewers of the program would agree that the time frame seems just about right for tracking the lives of this symbolic British sample. Perhaps, seven years corresponds to some currently obscure human psychological or developmental cycle?
Naturally, seven years is inexact – even Leo Szilard’s own life did not fall precisely into seven year units of professional activity. Yet seven seems near-enough as an analytic division, and nearer than the rival decimal-related measures. Even when people talk of cultural decades (e.g., the ‘naughty nineties’ or ‘roaring twenties’ in England) it can usually be found that there is a better-fit for seven years. The most famous recent decade – ‘the sixties’ actually falls more neatly into the optimistic technocratic early ‘swinging’ sixties up to about 1968; then a late-sixties/early seventies characterized by hippies and a more pessimistic counter-culture of psychoactive drugs and utopian protest.
In science, likewise, seven year units work well. Seven years is approximately the time spent at high school, and then the time taken for a traditional basic scientific training (e.g., the first degree and doctorate). The early post-doctoral period, building the knowledge to become an expert specialist, is also about seven years . After this, matters are less clear, and it would be interesting to perform empirical studies measuring career increments and professional transitions on a random group of scientists.
At any rate, there is already enough anecdotal evidence to support the idea that we should at least reconsider the reflex but un-thinking use of five year plans and evaluations, and the analysis of social, professional and personal trends by whole decade units. A new – and previously unconsidered – field of research beckons.
Thanks to Peter Andras for help with this idea.
 Cooper R. Szilard’s 10 commandments.
 F.L. Holmes, Investigative pathways, Yale University Press, New Haven (USA) (2004).