The angriest I’ve gotten in recent memory is when arguing with a friend about her bottled water drinking habits. It wasn’t that she drank the water that made me angry but that she didn’t want to consider any information that might suggest why she should or shouldn’t drink (as much) bottled water (if you’re scratching your head about why this may even be an issue, see for example http://science.howstuffworks.com/environmental/green-science/bottled-water4.htm). Her argument was along the lines of “I know how behavior change works. Information won’t lead to change in my behavior.” This is fascinating because it’s a failure in rationality that results from a misunderstanding of theories about failures in rationality, which have come to the attention of someone like her only recently due to the proliferation of behavioral economics.
Her reasoning is rooted in empirical research. One example of many from Nudge is where Minnesota taxpayers were given different types of information about complying with tax law. Only one group had a significant change in behavior. It was the one given a not-so-informative social cue, simply that “90 percent of Minnesotans already compiled, in full, with their obligations under tax law.” The generalization abstracted from this and many similar studies is that various social and perceptual cues are far more effective than information in producing a desired change in outcome. As a generality, I think it makes sense.
Consider this analogical experiment, which sounds like a horrible word problem come to life. A group of fifth graders were taken to a store that was having a sale. Two identical shirts were for sale, but one was 60% off while the other was 30% off with an additional 40% off the sale price. One group of children was given information about how to multiply percents. Another group of children were not given the information but rather the sign for the cheaper shirt was shown in bright colors. The result (OK, not a real experiment, but a reasonable guess): many more children in the second group got the cheaper shirt! So information sucks, right??
There are two problems with this conclusion that are much easier to recognize than the tax compliance one. First, the information is not properly presented. Fifth graders are not able to understand and apply math with percents after the presumably brief intervention provided by the experiment. The second problem is that the second group of children happened to be nudged to the cheaper shirt. Generalizing this idea of “let us be nudged” relies on some unnamed party to have the good intentions toward the nudgee, the right idea about how to nudge, and so on.
When we can understand and apply information, we become more powerful and free. If we know some math, we can calculate that the first shirt is 40% of the original cost, while the second is 42%, so the first is cheaper.
There is a limit to what we can know. We may be able to, by ourselves, calculate the better deal in a store. We cannot calculate the aerodynamics of the wings of an aircraft before hoping on board. We trust our lives to the engineers, the pilots, and the air traffic controllers when we fly on a plane. Even what we learn is trusted to the planning of curriculum designers, school board members, and teachers.
Back to the bottled water. My friend, who drinks the bottled water at work, was in some sense nudged into this habit by the free and readily available water. She is even nudged into some sense of environmental responsibility due to the recycling efforts at her workplace. But assuming that she has access to tap water and not an overly biased perception of the taste of tap water, there is little barrier to amending this habit.
Imagine my friend was a thoughtful and steadfast environmentalist and, somehow, wasn’t aware of any possible negative consequences of consuming bottled water. I imagine that she would have quickly devoured the information I presented and took action to change her behavior. But if she doesn’t have that disposition, she will not simply act on the information alone. Like the fifth graders at the store, she must learn. If she is to be convinced to change her behavior on this issue, she must learn facts about the effects of bottled water, and, more importantly, beliefs about the importance of the issue. But learning is difficult and time-consuming, and most people devote little if any conscious time to learning.
At one point she pointed to the company. “If I shouldn’t be drinking bottled water, they should do something about it.” But who is “the company”? Practically speaking, it’s probably the office manager who’s in charge of what is made available in the office kitchen. But even the office manager may get passed down instructions on what to offer based on central planning for all office locations.
My friend, empowered with knowledge, could try moving up the chain, talking to the office manager and then to the manager’s manager. In a company like hers, it’s likely that the office manager has a bit of flexibility. In the most positive front, there seems to be a movement in design towards allowing decisions to be made locally by end-users. But even if my friend is designing the office kitchen herself, before (and maybe even after) her argument with me, she would choose the bottled water. First she must learn.
EDIT 7/27 – changed the wording and added footnote about what she “must learn” since multiple people were confused.
 There is a middle ground between knowing math and nudging someone directly to the answer, which is better tools to do (“truthful”) math without a full understanding of the underlying concepts. I’ve discussed this in past weekly reviews in relation with Bret Victor’s Kill Math project. It didn’t fit into this post, but maybe I’ll bring it up again.
 “But a couple of very non-scientific, blind taste tests have found that most people — or most people in New York City, to be more accurate — can’t actually tell the difference between tap water and bottled water once they’re all placed in identical containers.” http://science.howstuffworks.com/environmental/green-science/bottled-water3.htm
 I think what was finally a bit convincing for her was the fact about how much water and fuel are used in manufacturing of the bottle, which is not offset by recycling it. I estimated that her consumption over a year could perhaps be enough to offset what someone needs to live, say in India.