For more than a quarter of a century, Raven has directed the Missouri Botanical Garden, the 141-year-old, 79-acre horticultural and research center that graces St. Louis, Missouri, U.S.A. Its collections range from roses to redwoods, from a center for home gardening to a Chinese garden to an architecturally intriguing geodesic dome that houses a moist jungle of tropical plants.

  Behind and beyond the Garden that the public sees is an institution that conducts and encourages  biodiversity research around the world: Energetic Garden staffers conduct inventories of plants in North, South, and Mesoamerica; several African states, and huge sections of Asia. The Garden is one of the collaborators in the Biodiversity Leadership Awards.

  Raven is ready and able to speak up for biodiversity any time, any place, and anywhere. During his tenure as home secretary of the National Academy of Sciences, he was instrumental in convening two landmark conferences on biological diversity — one in 1986 and one in 1997. In a recent interview, he ruminated on what he sees as some of the important issues facing the continuing struggle to inform the public about the seriousness of the biodiversity crisis. Some excerpts:

  Since then, our thinking has moved toward building sustainability —  in other words, managing the world’s biological assets in such a way that the future will have approximately as much to use for its own food, medicine, ecosystem services, or development or restoration and everything else, as we do now.

  People are coming to look on biodiversity not as lists of species that we have to try to preserve before they go down the drain — although that’s part of it — but as the whole living substance of our planet that allows us to manage it appropriately.

More scientists now seem to be making the economic argument for preserving biodiversity — for promoting what they call ‘environmental accounting.’ You have argued that ‘it is the moral dimension that should trouble us the most about the disappearance of such a large proportion of plants, animals, fungi, and microorganisms in such a short time.’ Is ‘environmental accounting’ an admission that people just won’t respond to the moral and ethical pleas?

  You can certainly make an argument about proven values. You want to preserve the wild relatives of, say, corn, because they’re going to be valuable. You can make an argument that you want to preserve redwood trees because they’re pretty to see.

  So there is an underlying economic rationale for saving biodiversity. On the other hand, if you start saying the world’s total value of ecosystem services is $50 trillion or $40 quadzillian, that’s almost meaningless. The world total of ecosystem services — the things that are provided by Nature — is everything. It has infinite value. If there were no services being provided by Nature, we’d all be dead.

  I don’t think you can put the really big conceptions into economic arguments, nor do they really help you much. But I think there’s plenty that can be said about things you do that are intelligent from an economic dollars and sense value, and they do help to make the point.

How would you assess the tensions that run through environmentalism now?

  We talk about ‘the economic community’ as being a kind of a relentless force, depressing and rendering less interesting and less vibrant and resilient everything in the whole world. The mirror image of that would be an environmental community which feels that nothing ever can or should be done about developing the world’s resources, because things are always better left alone.

  Now, in some sense, those are necessary point and counterpoint, two necessary opposing forces to a situation. But in another sense, neither one is really philosophically a satisfactory way to proceed. What we should be doing is making decisions in a more rational way, taking into account the evidence. And that’s what’s so difficult to do.

  We need a point in the confrontation where thoughtful people can balance the facts and make decisions based on what’s really going on. But maybe that just doesn’t work, human nature and human institutions being what they are. Maybe it always needs to be a kind of a confrontation.

  If so, let’s make it as informed a confrontation as we can.

Has science’s proper role in environmental protection changed? Should scientists be less reluctant to serve as advocates in the struggle to protect biodiversity?

  It’s really very gratuitous to say, ‘I’m just developing science, and other people can make decisions.’ You’ve got to be able to explain and to identify the issues in the science very clearly and very well if you want anybody to have the faintest hope of making any sensible decisions at all. . . .

  I think what scientists really need to do is to have the humility and the interest to explain, as clearly and objectively as they can, what it is that they’re doing, and what the choices are. If they’re willing to do that, then I think they’re doing a great public service.

  Scientists need to be willing in this modern world to realize that science takes place in a context, and they need to be willing to explain that context, and what they really know and what they really don’t know, clearly to the general public.

  It’s not just an offering that’s put out there in a void for the public to think about. It’s an informed set of observations, based on certain facts. If scientists use their knowledge to try to beat people into taking a certain course of action which they believe is right, in this modern world, thankfully, it won’t work. People are not ready to hear the high priests tell them what to do.

  People need to hear the scientists, but they need to hear them in the most thoughtful and clear and understanding way that they possibly can.