Nobody likes to wait, and we are willing to pay to avoid it. Expedited shipping, fast food and video streaming are all profitable because they reduce or eliminate that wait. You can test this by asking a group of people to choose between receiving £100 now or £110 in a year. Research shows a significant majority will choose the £100.
Author
- Daniel Read
Professor of Behavioural Science, Warwick Business School, University of Warwick
But why do many people choose not to wait, when it seems obvious that they would be better off doing so? Sometimes this impatience is just put down to irrationality, impulsivity or short-sightedness, but there is also a long tradition in psychology and economics that views impatience as, at least in part, a rational response to the world.
Perhaps the world of today, or perhaps the world in which we evolved.
Recent research proposes that our evolutionary history shaped our impatience, and uses mathematical models to show how it works.
The key idea is this. Imagine a large population of identical people who can choose between enjoying an early reward, or a larger reward later in time. An example might be choosing between two hunting grounds, one close and one further away.
The closer one is guaranteed to yield a small animal quite quickly, while the farther one is likely to yield a big animal but only after a considerable wait or a gruelling hunt. Another example might be eating the juvenile, smaller fruit on a tree or waiting a few months until the fruit are abundant and ripe.
Of course there is a catch. If the people wait too long for the large reward, there is a chance they won't live long enough to earn it. And even if they do, the ripe fruit might have vanished before they reached it, perhaps stolen by a rival.
As the authors of the recent study show, the animals (including humans) they model are better off taking the bird in the hand with even relatively small amounts of risk (you might not reach the birds) and uncertainty (there might not be two birds when you get there).
Although models like this are simplifications of the real world, they are valuable for conceptualising how evolution might have produced particular tendencies in humans and other animals. But this model doesn't do a lot to explain the human impatience we see now.
In most studies of choice over time, people display high levels of impatience even in settings where risk is all but eliminated, and when it is financially beneficial to be patient.
One explanation is that the evolved way of valuing the future is still in place even in modern humans. We act as if the world is uncertain and risky , as it would have been for hunter gatherers, even when it is not.
Good things come to those who wait
Another explanation might be that we struggle to think about how the £110 is better than the £100. There is a lot of evidence for this .
Consider, for example, an experiment I carried out in 2012 with psychologists Marc Scholten and Shane Frederick. Participants chose between £700 now or £700 plus £42 in one year.
When given the choice in terms of monetary amounts, people were impatient. But if the £42 was described instead as "plus 6%" they were much more patient.
People know that earning 6% a year is a great interest rate. But many people do not do the calculations and the extra £42 seems paltry compared to the £700.
Another result that does not fit this evolutionary story concerns people's responses to losses. Take a choice between paying a bill for £100 now or £100 later. A lot of people, often a majority, will prefer to pay the bill now. Indeed, some will prefer to pay £110 now rather than £100 later.
Yet the possibility that you will not have to pay a future bill, or that the bill might have vanished by the time you get to it (the indebted has forgotten or died) should make you want to delay paying bills as long as possible. The more common response is probably partly due to a fundamental aversion to debt , which does not have an obvious evolutionary basis, but it is associated with religiosity .
It remains to be seen if these complex preferences (such as patience for negative outcomes) can be explained by the process of natural selection, or if it is something that came later in human development.
Evolutionary theory is an essential tool for thinking about the foundations of human decision making. The modern world is, however, very different from the environment in which we evolved.
Daniel Read receives funding from the ESRC.
