The last few years have seen an intensification in the long running debate about the underlying rationale(s) for biodiversity conservation. In Georgina Mace’s terminology, is conservation about nature for itself, nature despite people, nature for people, or people and nature?

Some argue that there is no need to make choices here – conservationists should simply select the appropriate tool from the menu of rationales available to them to fit their particular needs. For example, a recent paper by Richard Pearson argues that different rationales should be applied to justify conservation depending on the spatial extent and biological level of the thing to be conserved. So, arguments about the benefits to people from pollination services apply well for populations of honeybees at the local scale, whereas arguments about existence value apply well to charismatic species that are globally threatened.

This ‘ecumenical approach’, drawing on multiple rationales to support conservation, seems to be very popular with conservationists. For example, in the opening plenary of the recent Student Conference on Conservation Science in Cambridge, Taylor Ricketts ran an audience poll offering a similar set of choices. The overwhelming winner in the room was the option that sought to justify conservation two ways – for the intrinsic value of biodiversity and anthropocentric value arguments (although interestingly Ricketts placed himself in the ‘anthropocentric arguments are a means to the end of protecting intrinsic value’ category).

The idea that it is possible to justify conservation in multiple ways is appealing in theory, and it may even work some of the time. However, unfortunately there are two problems that mean it can’t work all of the time in practice. Firstly, there is the risk of crowding out of motivations, in which an instrumental argument about material benefits to people erodes pre-existing moral norms around intrinsic value (although for balance – crowding in, where the opposite happens, is also possible).

Secondly, different rationales for conservation can lead to different management practices, which may not be compatible. In Ricketts’ talk, he described some of his own work showing that in a Costa Rican forest / coffee farming landscape it pays financially to retain small and isolated fragments of forest because the insects they contain provide crucial pollination services to neighbouring farms. So from an ecosystem services based rationale for conservation, protecting these small fragments is crucial. However, what would happen if an intrinsic value argument was being used in the same landscape, with a large predator like jaguar as the focus? Suddenly it might be the largest patches of habitat, far away from farms, that would be the priority, in order to provide the spaces and prey densities needed by a top predator. If it is possible to keep all forest habitat in Costa Rica then both arguments can be applied synergistically. But if something has to be lost, which is very often the case in conservation, then one of these arguments will have to give – a trade off must be made. Which is it going to be? Do we want pollination or carnivores? Do we care more about crop yields, or rare species?

The frequency of trade-off situations in conservation is very well established. And yet I still see the optimistic narrative about the synergy of diverse rationales for conservation presented all the time.  This ‘multiple complementary rationales’ narrative seems to me just another version of conservation’s obsession with the idea of win-win. With intrinsic values and anthropocentric values in their toolkit, conservationists seemingly feel empowered to win every argument.  I don’t think this is just a PR stunt – this narrative is frequently used when conservationists are talking to each other as well. So why won’t the myth of win-win in arguments for conservation go away?

Perhaps it is too compelling? The idea that conservation justifications dovetail neatly, so that conservation can deliver benefits for people and wildlife at the same time, is a comforting and heartwarming story. Maybe conservationists want it to be true so badly that they can’t bear the truth that this rarely happens, even when faced with mounting evidence. Or, perhaps it is too effective? As a message to send donors and policy makers, win-win narratives are much more likely to raise funds and shift decisions than complicated trade-off stories. As Bruno Latour famously said, “if we want to move ahead quickly while remaining precise, nothing is so concise as a myth.”

I think conservation must do better than this. The sector needs to get real about trade-offs between rationales for conservation and the difficult choices that they entail, rather than hiding behind wishful thinking about complementarity. Choices need to be identified, argued about and made, even if that means getting right down to the value systems on which conservation ideas are built. This is why the New Conservation debate, which engages with some of these underlying rationales, is more than just navel gazing or chest beating, even if the content and tone of the arguments may suggest otherwise. It is a debate about what conservation is for, which in turn changes how conservation should be done. What could be more important?