Cognitive bias plays an important role when it comes to behavior change related to sustainability. Understanding cognitive biases in decision making can help design interventions that align with people's inherent biases and promote sustainable choices. For instance, displaying reusable bags prominently and creating a community norm around their use can encourage individuals to adopt more environmentally friendly behaviors. Ultimately, the goal is to foster collective behavior change through a design-informed approach.
Here’s a question you might not expect: why should you probably use a reusable grocery bag even though it is probably worse for the planet?
When thinking as designers, we need to consider human behavior. People do not make choices purely off of conscious thoughts which are the result of cognitively processing information in a rational way.
Maybe this seems obvious to you.
But in conversations about climate change you will often encounter the admonition that we need to “listen to the science”. And we should! But we also should recognize that understanding information is not enough to change behavior.
If perfect information and cold facts were enough to drive decision making and thereby behavior, then advertising would not work and there would be a lot less need for design.
So what’s happening when listening to facts doesn’t result in a behavioral change, even when one might seem warranted?
At the intersection of psychology and economics there is a line of research into what are called cognitive biases. These are patterns of thinking and behavior which are generalizable across human populations and which represent departures from “rational” decision making. We are imperfect beings with limited information and limited capacity to process information, so if we are to design for behavior change we have to design for people as they are, not for people as we imagine or wish them to be.
How might an understanding of cognitive biases help us design for changing behavior around sustainability in the choices of shoppers in grocery stores, for instance?
Single use plastics like disposable grocery bags consume resources, are made of fossil fuels, and contribute waste to landfills.
So your first thought might be to reduce use of single use bags by simply not offering them! But this would be super inconvenient for your customers, and while you might change their behavior, it might be to drive them to shop at one of your competitors. Design sits at the intersection of technological possibility, human design, and business viability. So this idea neither works for the proprietor of the single store, nor does it actually change the impacts of the consumption patterns of the shoppers.
Maybe your next thought is to launch an informational campaign in your store where you’ll regale your patrons with the harms and horrors of single use grocery bags. Load them up with statistics and data. But from a perspective informed by an understanding of human cognitive biases, which is to say an empathetic perspective on your customers’ individual lived experience, you can probably quickly see that this intervention will also not have the desired effect. Your customers have confirmation bias - and retain information that already conforms with our world view and even if they stop in their busy day to listen they are unlikely to change their view on any topic.
But let’s imagine someone who does stop and read. Someone who really nerds out about the environmental impact of reusable bags.
They would quickly learn that most individual reusable bags have a higher environmental impact - in terms of things like freshwater usage and contributing to greenhouse gas emissions - than each single super thin and light single-use-bags. So a reusable bag needs to be used several times - the amount varies significantly depending on what the reusable bag is made of - for the net impact on the environment to be better than just using single use bags. And most people simply do not use the reusable bags that they have bought enough times before likely stuffing them in a closet for their use to actually be less impactful than if they had just stuck with the single use bags.
But let’s zoom back out. Our goal as the proprietor of this store wasn’t to stop providing single use bags, it was to nurture sustainability in our clientele.
With our design approach, informed by an understanding of cognitive human factors, maybe we put the reusable bags prominently on display at the checkout counter and give them away or sell them at reduced cost. We have a strong drive to be in harmony with people we see around us. So just seeing the reusable bags — so highly associated with sustainable behavior — and seeing more people using them establishes a norm that this is a community that cares about environmental impacts.
So actually, by the numbers, if you buy reusable bags like most people you should probably not use reusable grocery bags at the grocery store. But if you think like most people, you probably should use a reusable grocery bag to drive collective behavior change in a design informed way.