Discussion about climate change often focuses on the future. People talk about the world we’re handing to our children and grandchildren. They worry about food, water, and physical security, and scientists work to predict what will happen to ecosystems around the globe.

But what if we talked about the past instead—about getting back to the way things used to be? Researchers Matthew Baldwin and Joris Lammers at the University of Cologne, Germany, got volunteers to do just that in a series of experiments. They found that framing discussions and messages this way may help reduce climate change skepticism among political conservatives, who tend to be less likely than liberals to accept the scientific consensus on human-caused climate change.

Baldwin and Lammers took cues from previous research, which suggested that conservatives tend to be concerned with preserving the past, while liberals would like to replace current systems with ones they think would be better. As such, they hypothesized that conservatives may be resistant to environmental messaging that focuses on disrupting the status quo because of speculations about the future. This would mean that climate change skepticism may not result as much from “an inherent disbelief in scientific evidence,” they write, but rather to this difference in emphasis and perspective.

In their study, published in the Proceedings of the National Academy of Sciences, Baldwin and Lammers ran a series of experiments on Amazon Mechanical Turk to test the hypothesis. In the first experiment, the researchers gave participants a message about a current social issue and told them it was written either by a liberal or a conservative. Half of the participants got a future-focused message, like “Looking forward to our nation’s future, there is increasing traffic on the road.” The other half were given a past-focused message, such as “Looking back to our nation’s past, there was less traffic on the road.”

After reading the message, the participants took a survey about it and their opinions on climate change and the environment. Participants who reported that they were conservative rated the past-focused message more positively and showed more pro-environmental attitudes in the survey. Interestingly, the political affiliation of the message-writer didn’t seem to change this effect.

In another experiment, the researchers looked at a different kind of messaging: photograph pairs. For instance, participants were shown a photo of a dried-up river basin alongside a river full of water. Researchers told some participants that the full river was from the past and the dry one was the present; they told the rest that the full river was from the present and the dry one was a prediction of the future. Conservatives who viewed the past-focused pictures showed more concern about the environment than those who saw the future-focused pair.

In a final series of experiments, the researchers tried to examine the potential real-world impact of this strategy. They chose 46 real environmental charities and had MTurkers rate whether they were past- or future-focused. The participants rated the charities, as a group, as overwhelmingly future-focused—clearly a problem for persuading past-focused conservatives.

Next, the researchers gave participants $2 and pointed them to the most and least future-focused charities rated earlier. The researchers told the participants they could either donate or keep the money. Liberal participants gave equally to the most and least future-focused charities. Conservative participants, on the other hand, gave less money to the future-focused charities.

When researchers tossed a cancer research charity into the mix, conservative participants gave around the same amount to it as they did to past-focused environmental charities. Last, when the researchers invented two charities with different emphases—“Restoring the planet to its original state” vs. “Creating a new earth for the future”—conservatives donated more to the past-focused charity, while liberals donated more to the future-focused one.

Overall, the results suggest that the difference in focus narrowed the gap between conservatives’ and liberals’ environmental attitudes. “Paradoxically,” the researchers write, “it is the past that may be critical in saving the future.”

Still, while the charity donation experiments are promising, in reality, the strategy may not be enough. Environmental conservation policies often involve substantial compromises: trying to mitigate climate change damage often means changing industries or other ways of life. The tasks in the experiments didn't involve these kinds of costs, so we do not know whether a change in message focus would have a strong enough effect to outweigh them. Moreover, this particular subset of participants didn't include the most vehement opposers of climate change facts, who perhaps would be less likely to be swayed by a change in message—and more influential in spreading a culture of denialism.

There's also the question of why conservatives found the material more persuasive: did it tap into their desire to preserve the past, as Baldwin and Lammers suggest? Or could it be because the past-focused materials showed evidence about what has already happened, which is more persuasive than predictions about what may happen?

Regardless, the study offers an interesting reminder that the liberal-conservative divide can be bridged if each side tries to understand how the other half thinks.

PNAS, 2016. DOI: 10.1073/pnas.1610834113 (About DOIs).