A change would do you good
On the problem with 5-year super-optimism and 15-year extra-pessimism
Human misjudgments come in all sorts of flavors. Charlie Munger's famous speech and extended essay on the subject documents 25 such tendencies that lead us to faulty conclusions. Similar tendencies of the mind cause us to make common mistakes about the future. One of those might be termed the "5/15 Rule".
■ Forecasts of change are often too optimistic (that is, they assume too much will change) on a five-year horizon. But they are often too pessimistic on a fifteen-year horizon (that is, they assume things will remain too much the same). Hence, 5/15. Optimism and pessimism are relative things, of course; one person's progress might be another person's regress. But in general, things tend to get better in a free and open society: Material well-being improves, technology moves forward, and freedoms are newly enshrined into law. For most purposes, then, we look forward to change since on balance it brings about a better quality of life.
■ Consider progress in space flight: Between 2006 and 2011, there were 21 launches of NASA's Space Shuttle, culminating with the retirement of the program in July 2011. Nothing technologically substantial was different between the first of those flights and the last. But between 2006 and 2021, an entire industry of private space flight emerged, with reusable rockets that land vertically and tourists like a 90-year-old William Shatner going to space.
■ In consumer technology, Facebook opened to universal access in 2006, and the iPhone was introduced in 2007. By the end of 2011, Facebook claimed a large number of users -- some 845 million, but the experience and impact of the site remained largely unchanged. In early 2012, The Guardian could unironically submit that "Digital analysts predict this will be the first election cycle in which Facebook could become a dominant political force." But 15 years after 2006, Facebook's impact on electoral activity was so great that Mark Zuckerberg was called to testify before Congress for a joint hearing on "Social Media's Role in Promoting Extremism and Misinformation" -- a session precipitated by the January 6th riot at the Capitol.
■ Over the five years from 2006 to 2011, America's per-capita emissions of carbon dioxide fell by about 12%. But over 15 years, they fell by 30%, in no small part because of developments like an increase in wind-power generation from 11,575 megawatts to 122,465 megawatts. As technologies improve incrementally and industries grow to scale, factors like price can change by orders of magnitude -- like the 70% to 80% decline in the cost of photovoltaic solar power generation in just one decade.
■ Within a five-year window, political change tends to move like molasses. A seat in the U.S. Senate isn't even up for re-election before six years are over, and even in the House of Representatives, the mean tenure was 8.9 years as of January 2021. Over any given five-year period, very little changes about the makeup of Congress. But on a 15-year basis, the national government can change quite radically: In 2006, Barack Obama had been in the Senate for just a year. Fifteen years later, not only had he left the Senate and broken the color barrier in the Article II branch of government, but so had Kamala Harris (who in 2006 was a district attorney).
■ Margaret Thatcher once said, "I do not believe that history is writ clear and unchallengeable. It doesn't just happen. History is made by people: its movement depends on small currents as well as great tides, on ideas, perceptions, will and courage, the ability to sense a trend, the will to act on understanding and intuition." (Note that nine years before she won the job, Thatcher said "There will not be a woman prime minister in my lifetime".) It may be counterintuitive to recalibrate our expectations so that we can accept how slowly things might change in five years and how dramatically in fifteen. But given how quickly a snail's pace can accelerate to supersonic speed, a 5/15 Rule is well worth keeping in mind.