It is something of a commonplace to note that the system of Apostolic succession all but guarantees that presidents of the LDS church are quite old by the beginning of their time in office. Thomas S. Monson (barring unprecedented changes in Apostolic succession) will be no exception; he is currently 80 years old. What this means substantively is a complicated issue. Medical developments stretch people’s lives substantially compared with past centuries, and they often also help people retain higher levels of physical and emotional functioning than would have been the case for people at a similar age in past generations.
As a matter of historical comparison, it may be worth pointing out that, while Monson is old, he is by no means unusually old for an LDS church president. Six previous presidents were older than Monson at the moment they were ordained: Hinckley, Hunter, Benson, Fielding Smith, Snow, and Woodruff. In fact, the average age at ordination of Mormon church presidents (excluding the two early outliers, Joseph Smith and Brigham Young) is about 78; Monson is only barely above the mean. So while Monson is elderly by any standard at the beginning of his term in office, he is by no means exceptional.
However, this raw comparison of ages obscures as much as it reveals, specifically because of changes in medicine and life expectancy. If we adjust for contemporary life expectancy, Monson is no longer merely about the normal age for a beginning Mormon church president; he is instead one of the youngest beginning church presidents in history. The exact statistics and fine details of ordering of course depend on exactly how one measures life expectancy, and there are many such measures. However, without getting too picky, the following is roughly true for a variety of different operationalizations.
- Monson is one of the youngest starting church presidents since the 19th century, relative to life expectancies. Heber J. Grant, who was 62 when he was ordained, was clearly younger in relative terms than is Monson. Joseph F. Smith (age 62, as well, but a few years earlier and therefore during a period of lower life expectancy) was also a bit relatively younger than Monson. Harold B. Lee (age 73) was either fractionally younger or fractionally older than Monson in relative terms, depending on the specific measure of life expectancy chosen. All other church presidents since the 19th century have been older, relative to life expectancy, than Monson is now.
- The only 19th-century leaders who were younger, relative to life expectancy, when they became church presidents than Monson is today were Joseph Smith, Jr., and Brigham Young. Since the system of Apostolic succession was instituted with Young, selection effects have guaranteed that Mormon church presidents will almost always be older than contemporary life expectancy at the moment they are ordained.
- Monson is four years younger in absolute terms than Hinckley was when he assumed the presidency of the church. This is no guarantee that Monson will live to Hinckley’s ripe old age. Yet we shouldn’t automatically assume that he won’t. Conditional on health and circumstance, Monson is well-positioned to serve a lengthy period in his probable new calling.