Forty years after C.S. Holling gave academic status to the word "resilience," the concept has found a home in several different disciplines.
From ecology, where Holling first defined resilience in 1973 as the measure of a system's ability to maintain its operational integrity, the term is now cropping up frequently in economics, psychiatry, robotics, medicine, military strategy, and many more disciplines.
Results of a 2013 World Economic Forum survey, of 1,000 experts in academe, government, and industry, on nations’ resilience to interconnected global risks.
Less clear, though, is whether "resilience" is a term of real scientific precision, or if it's just flittering through academe, a chameleon noun most popular as a lazy tool of opportunistic imagery.
Even Holling—now retired as a professor of ecological sciences at the University of Florida—can't say his work has led to a common understanding of the idea across fields. He has made his most determined hunt for commonality by working with economists, driven by the idea that the 2007-8 financial collapse was similar to numerous environmental disasters in showcasing society's chronic tendency to misread the true linchpins in a system. But five years of organizing conferences involving leading ecologists and economists have largely led him to frustration.
The problem, by Holling's account, is that too many economists pay little or no attention to such tipping points, preferring to emphasize strategies that grow systems rather than dwell on their potential instabilities.
"There was never a good bridging between the ecosystem ecology of resilience and the economic theory of efficiency and growth," Holling says of his global series of seminars and workshops. "It didn't really happen."
Others make similar observations. Several researchers at the University of Melbourne, in Australia, recently completed a study comparing the understanding of resilience between the social and natural sciences.
Their findings, published in March in Environmental Research Letters, identified substantial differences both in methodological approaches and in fundamental understandings that prevented finding common ground.
The University of Melbourne team compiled a list of a dozen different definitions for resilience found in published papers in the ecological and social sciences, covering concepts that include coping, recovering, adapting, withstanding, and self-organizing.
"It just means different things now to different people in different fields," said one of the authors, Barbara J. Downes, a professor of resource management and geography.
The simple fact that tipping points, or thresholds, when they are reached, often surprise experts in a field shows the lack of widespread academic development of the concept of resilience, says David D. Briske, a professor of ecosystem science and management at Texas A&M University.
"It's become widely used, and it's captured, certainly, a lot of imagination and attention," Briske says of the term. But "when it comes down to applying it or operationalizing it or quantifying it, it becomes extremely difficult."
That doesn't necessarily mean the idea of resilience won't eventually become meaningful in more disciplines. To Holling, in fact, an academic field's ability to understand resilience may be a good measure of its maturity.
One example, he said, involves Hyman P. Minsky, a longtime professor of economics at Washington University in St. Louis who died in 1996. Minsky's understanding of the fragile nature of financial markets, and the risk of their sudden collapse, proved prescient in 2007.
An economist who got even more recognition was Elinor Ostrom, a professor of political science at both Indiana University and Arizona State University. Ostrom, who died last year, won a share of the 2009 Nobel prize in economics for improving the standard analyses of how well common property, including the natural environment, is managed by societies.
For example, she studied life on the boundaries of a national park in the developing world, where the needs of very poor people conflict with conservation priorities, says Molly Miller Jahn, a professor of agronomy at the University of Wisconsin at Madison.
"She thought she was studying political theory, but what she was actually studying was sustainability, or you could call it resilience," because of the intersecting patterns she was uncovering, Jahn says.
There are other instances of resilience finding common understandings across disciplines. Mark E. Servis, a professor of clinical psychiatry at the University of California at Davis, says his field recognizes resilience themes traditionally associated with ecologists. They include ideas such as diversity, flexibility, and strength in terms of personalities and neuropsychological characteristics, Servis said.
And engineers may not use the term resilience, said Stuart L. Pimm, a professor of conservation ecology at Duke University, but they do understand an eigenvalue—a mathematical construct for measuring the long-term probability of a particular event happening, such as when the routine vibration of a bridge from winds and other pressures might lead to its collapse. As such, Pimm said, an eigenvalue is essentially a measure of resilience.
Speaking a common language across disciplines is just part of the challenge of making use of resilience theory, according to Holling and other experts. The next big step, he said, will involve finding ways to balance and mesh the competing theories of how best to tackle a particular problem.
How might a wheat farmer, for example, anticipate the exact mix of genetic variations that both protects from pests and affords long-term sustainability and profitability?
"Research on resilience, especially in the social-ecological context, has been fairly theoretical," says F. Stuart Chapin III, professor emeritus of ecology at the University of Alaska at Fairbanks. "My sense is that the next major developments in resilience will be to come up with predictions that are more useful to managers than those that have emerged to date."