Life Expectancy - Life Expectancy Vs. Life Span

Life Expectancy Vs. Life Span

Life expectancy is often confused with life span to the point that they are nearly synonyms; when people hear 'life expectancy was 35 years' they often interpret this as meaning that people of that time or place had short life spans. One such example can be seen in the In Search of... episode "The Man Who Would Not Die" (About Count of St. Germain) where it is stated "Evidence recently discovered in the British Museum indicates that St. Germain may have well been the long lost third son of Rákóczi born in Transylvania in 1694. If he died in Germany in 1784, he lived 90 years. The average life expectancy in the 18th century was 35 years. Fifty was a ripe old age. Ninety... was forever."

This ignores the fact that the life expectancy generally quoted is the at birth number which is an average that includes all the babies that die before their first year of life as well as people that die from disease and war. The genetics of humans and rate of aging were no different in preindustrial societies than today, but people frequently died young because of untreatable diseases, accidents, and malnutrition. Many women did not survive childbirth, and individuals who reached old age were likely to succumb quickly to health problems.

It can be argued that it is better to compare life expectancies of the period after adulthood to get a better handle on life span. Even during childhood, life expectancy can take a huge jump as seen in the Roman Life Expectancy table at the University of Texas where at birth the life expectancy was 25 but at the age of 5 it jumped to 48. Studies like Plymouth Plantation; "Dead at Forty" and Life Expectancy by Age, 1850–2004 similarly show a dramatic increase in life expectancy once adulthood was reached.

Read more about this topic:  Life Expectancy

Famous quotes containing the words life, expectancy and/or span:

    I can entertain the proposition that life is a metaphor for boxing—for one of those bouts that go on and on, round following round, jabs, missed punches, clinches, nothing determined, again the bell and again and you and your opponent so evenly matched it’s impossible not to see that your opponent is you.... Life is like boxing in many unsettling respects. But boxing is only like boxing.
    Joyce Carol Oates (b. 1938)

    If I had my life over again I should form the habit of nightly composing myself to thoughts of death. I would practise, as it were, the remembrance of death. There is no other practice which so intensifies life. Death, when it approaches, ought not to take one by surprise. It should be part of the full expectancy of life. Without an ever- present sense of death life is insipid. You might as well live on the whites of eggs.
    Muriel Spark (b. 1918)

    Life’s brief span [vitae summa brevis] forbids us to enter on far-reaching hopes.
    Horace [Quintus Horatius Flaccus] (65–8 B.C.)