Black Swans and Green Elephants: Time Inconsistency, Salience, and the Tragedy of the Horizon
“When the well is dry, we know the worth of water.” These were Benjamin Franklin’s cautionary words over 250 years ago. March 22, 2018, is World Water Day, and this year the residents of Cape Town will be feeling the poignancy of his words as they approach “Day Zero”—the day the taps will be turned off (July 9, 2018). Their three-year drought has caused households and businesses to take radical measures to reduce water consumption. Cape Town will not be alone, as the UN warns that by 2030, global demand for fresh water will exceed supply by 40%.
Franklin’s words remain as true today as they were then, because we humans are irrational in how we quantify value and risk at different points in time. This is evidenced by behavioral finance experiments in which it was observed that losing something makes us approximately twice as miserable as gaining the same thing makes us happy. However, preserving what we have is also subject to biases, as we tend to undervalue future risks, particularly if there is a short-term “cost.” Humans are prone to temptation, procrastination, and status quo bias, which explains why so many New Year’s resolutions are broken and why vices such as smoking and drinking remain prevalent, despite our knowledge of the negative consequences.