And then there is the problem of complexity. The earth’s interior, atmosphere, oceans, and life interact with one another and with the sun’s energy and with a host of cosmic influences in a probabilistic stew that is far beyond our mathematical reckonings. Each is a system with its own complex behaviors, as are humans (and scaling up), organizations, societies, civilization, and the biosphere. So complex is the world we inhabit that we cannot predict with certainty even the behavior of one single human being, or the exact motions of one single electron in orbit about its atom. Never mind trying to predict matters comprising as many variables as global warming, Middle East relations, or the fate of food resources. Science has quantitatively confirmed the adage that the whole is combinatorially greater than the sum of its parts.

Cause and effect, we find, is rarely related in a simple, linear way. A little more input does not always translate into a little more output. The laws of the universe are not simple linear equations written by some simplistic God. They are complex formulas with innumerable variables working in many dimensions, simultaneously influencing and influenced by innumerable other variables, and continually feeding back upon each other at varying rates. Properties emerge from these interactions that are far beyond our predictive powers. Nothing that we know about the explosive properties of hydrogen or the flammable characteristics of oxygen would allow us to predict that, when coming together, these two elements produce the miracle molecule, water. How less percipient are we about the ways in which the earth’s geochemical processes interact with the millions of living species and that little emergent property, human consciousness. What a mix that is. How do we react, for instance, when oil becomes too expensive to even drill, or when economic globalism sputters and stalls, or when famine strikes our homeland? The historian Niall Ferguson reminds us, “When things go wrong in a complex system, the scale of the disruption is nearly impossible to anticipate. There is no such thing as a typical or average forest fire, for example.”[i]

To make matters more difficult for us, these nonlinear laws of nature have what are referred to as tipping points or thresholds. Reach these points in the calculus of our behavior and suddenly the universe seems to run by a whole new set of equations. Natural gas may leak from a kitchen stove and nothing happens when one lights a match. Strike it again thirty minutes later and the whole house explodes. In this system, a threshold was reached with the variables of methane, oxygen, space, time, and energy (the flame). Or take the much-maligned postal worker who for years tolerates the injustices, stresses, and humility of his job until one day he cannot bear them any longer and, with seemingly little provocation, he shoots several coworkers. Or, similarly at another level, population pressures, drought, economic crisis, and a hundred years of colonial and African history between Tutsis, Hutus, Germans, Belgians, and the French in Rwanda suddenly exploded around 8:20 p.m. on April 6, 1994 when a private plane carrying the Rwandan president Juvénal Habyarimana was shot down by two surface-to-air missiles, triggering a mass homicide where eight hundred-thousand people were slaughtered within the space of a few months.[ii] Or tensions fester between Iraq and Kuwait over oil fields along their common border until a threshold is reached in 1990, and Iraq invades Kuwait, which then releases an invasion from other interested players. Or the Soviet Union endures the contradictions of its system and the adversities of the 20th century for seventy plus years, and then, in relatively easy times, suddenly implodes. Or stars like our sun enjoy long lives of relative stability until the moment that the hydrogen fusion process drops below some threshold value and the star collapses, marking the start of its death cycle and the likely end of any remaining life on earth.

Today, the most consistent scientific warnings about a threshold concerns global warming. Four hypothetical tipping points related to Earth’s continued warming this century include the sudden collapse of the Gulf Stream, a runaway collapse of the Amazon rain forest, a mega-release of methane from the tundras and sea floor, or a rapid unraveling of the ocean ecosystems due to a geologically unprecedented acceleration of ocean warming and acidification.[iii] Involving the whole planet, living and nonliving, the incremental increases of trapped solar energy in our atmosphere, lands, and oceans include so many variables feeding back upon each other that it makes Poincare's insolvable three body problem look like simple algebra.[iv] Simply put, it is too complex.

However, we have witnessed the tipping point effects of our behavior on a smaller scale: (1) The sudden re-emergence of diseases such as cholera, the expansion of malaria and chikungunya due to globalized transportation and weather and climate changes, and the emergence of new diseases such as AIDs and Ebola from once remote jungles, (2) Cultural eutrophication of fresh water lakes and the rising frequency, number, and size of dead zones in coastal ecosystems, (3) Sudden fishery collapses in the oceans due to over-fishing, (4) Loss of local species due to the introduction of alien organisms, and (5) Localized climate changes caught in a positive feedback cycle, where, for instance, decreasing rainfall reduces forest plant mass, which decreases the evapotranspiration into the atmosphere, which decreases the water available for clouds and rain, leading to further deforestation. These examples are taken from the Millennium Ecosystem Assessment's (2005) Ecosystems and Human Well-being: Synthesis. In example (2), cultural or anthropogenic eutrophication is a highly accelerated version of a natural process affecting freshwater lakes. Excess nutrients from chemical fertilizers, principally, wash from rivers into large bodies of water and stimulate excessive plant growth (called algal blooms). When these plants die, the bacterial decomposers that feed on the plants experience a population explosion, depleting dissolved oxygen levels (this is called hypoxia or anoxia, depending on the severity). All the other organisms either flee the area or suffocate and die. When this process occurs along the coasts, the usually biologic-rich waters are turned into “dead zones.”[vi] Worldwide, there are now some four hundred dead zones. The one in the Gulf of Mexico—the sink for the Mississippi River—is reputed to be as large as the state of New Jersey and lasts for eight months at a time. In example 5), evapotranspiration refers to the process by which water is evaporated from lakes, soil, etc. and is transpired from trees. On a hot day, a large tree can transpire as much as 100 gallons of water from its leaves into the atmosphere. The Smoky Mountains in the Southern Appalachian Mountains derive their name from the blue haze one sees over them, the visual effect caused by the millions of tons of water being transpired from all the leaves of the trees on a summer day.[vii]

Could it be that the many breakdowns of local ecosystems is a symptom of a larger-scale unraveling of Earth’s biospheric ecosystem? Is humanity nearing some planetary tipping point? Or, is the Earth actually far more resilient and our species far less potent than we imagine?

The complexity of nature’s seemingly infinite number of systems, of their interactions, and of threshold events will create a future as unpredictable as any history has ever offered. Since the 1970s at least, scientists have correctly projected, from past and existing events, the continued increase of the human population, of the global economy, energy use, and CO2 emissions; the continuing destruction of rainforests, farmland, and coral reefs; and the crises of extinctions, clean water, and climate change.[viii] And they got plenty wrong as well.[ix] In a 1962 article in the journal Science, Raymond Bouillenne correctly projected that there would be six billion people worldwide in 2000, but badly miscalculated the Russian population when he predicted that, “In 1990 there will be 400 million Russians.”[x] As it turned out, by 1990 there were less than 300 million people living in the Soviet Union, and only about half of them were Russians. The Russian population has been dropping ever since. “People predicted the fall of the Chinese Communist Party in 1989, and it didn’t happen… People did not predict the fall of the Soviet Union in 1991, and it did happen…”[xi] Robert Malthus famously predicted in 1798—about the time that the world population was hitting its first billion mark—that, due to agricultural limits, population could not increase much more. There are seven billion of us now, and counting. And in 1968, the biologist Paul Ehrlich proclaimed that, “The battle to feed all of humanity is over. In the 1970s hundreds of millions of people will starve to death in spite of any crash programs embarked upon now. At this late date nothing can prevent a substantial increase in the world death rate ...”[xii] And no, that did not happen either.

Complexity makes specifics difficult to predict, but the general reality to which Civilization is tending, the “attractors” in the language of dynamical systems theory, can be outlined.[xiii] Very likely, droughts and heat waves will destroy crops in the coming decades and people will continue to go hungry. Far more risky to predict is where, when and how destructive the events, and who specifically will suffer.

[i] Ferguson (2010, March/April).

[ii] Diamond, J. (2005), Boudreaux (2009), Gourevitch (2009), Jolis (2010), Snow (2014).

[iii] Flannery (2005) Holthaus, E. (2015, August 5) The Point of No Return: Climate Change Nightmares Are Already Here. Rolling Stone.

[iv] In 1887, Oscar II, King of Sweden, in honor of his sixtieth birthday, sponsored a mathematical competition. Henri Poincaré, a Frenchman, won the contest with a paper concluding that the interactions of even just three astronomical bodies could not be exactly solved. Since present positions depend on initial conditions that may be below the sensitivity of the measurements, predictions can be greatly in error and appear “chaotic.” At that point, the science of complexity is said to have been born. Since then, science has, in great part, gone from trying to discover nature’s fundamental and simple laws to modeling the complex interactions of nature’s many variables.

[vi] (Malakoff, 1998; Vance, 2001; Ferber, 2004; Sverdrup et al, 2005).

[vii] (Welch, 2002).

[viii] Ehrlich (1967), Meadows et al. (1972, 2004), Holdren and Ehrlich (1974), Catton (1982), Pimentel et al. (1973, 1992, 1995, 1997), Kendall and Pimentel (1994), Daily et al. (1998), Postel (1997, 1998, 1999).

[ix] For the many predictions scientists have gotten wrong, read Maurice and Smithson (1984) or Baily (1993), or a concise version in www.reason.com/rb/rb020404.shtml. Included are predictions of mineral exhaustion, projected high oil prices, population explosions and crashes, famines and species extinctions.

[x] Bouillenne (1962).

[xi] Fallows (2011).

[xii] Ehrlich (1968:xi).

[xiii] For example, Eckmann and Ruelle (1985), IPCC (2014).

[i] Ferguson (2010, March/April).

[ii] Diamond, J. (2005), Boudreaux (2009), Gourevitch (2009), Jolis (2010), Snow (2014).

[iii] Flannery (2005) Holthaus, E. (2015, August 5) The Point of No Return: Climate Change Nightmares Are Already Here. Rolling Stone.

[v] However, we have witnessed the tipping point effects of our behavior on a smaller scale: (1) The sudden re-emergence of diseases such as cholera, the expansion of malaria and chikungunya due to globalized transportation and weather and climate changes, and the emergence of new diseases such as AIDs and Ebola from once remote jungles, (2) Cultural eutrophication of fresh water lakes and the rising frequency, number, and size of dead zones in coastal ecosystems, (3) Sudden fishery collapses in the oceans due to over-fishing, (4) Loss of local species due to the introduction of alien organisms, and (5) Localized climate changes caught in a positive feedback cycle, where, for instance, decreasing rainfall reduces forest plant mass, which decreases the evapotranspiration into the atmosphere, which decreases the water available for clouds and rain, leading to further deforestation. These examples are taken from the Millennium Ecosystem Assessment's (2005) Ecosystems and Human Well-being: Synthesis. In example (2), cultural or anthropogenic eutrophication is a highly accelerated version of a natural process affecting freshwater lakes. Excess nutrients from chemical fertilizers, principally, wash from rivers into large bodies of water, stimulating excessive plant growth (called algal blooms). When these plants die, the bacterial decomposers that feed on the plants experience a population explosion, depleting dissolved oxygen levels (this is called hypoxia or anoxia, depending on the severity). All the other organisms either flee the area or suffocate and die. When this process occurs along the coasts, the usually biologic-rich waters are turned into “dead zones” (Malakoff, 1998; Vance, 2001; Ferber, 2004; Sverdrup et al, 2005). Worldwide, there are now some four hundred dead zones. The one in the Gulf of Mexico—the sink for the Mississippi River—is reputed to be as large as the state of New Jersey and lasts for eight months at a time. In example 5), evapotranspiration refers to the process by which water is evaporated from lakes, soil, etc. and is transpired from trees. On a hot day, a large tree can transpire as much as 100 gallons of water from its leaves into the atmosphere. The Smoky Mountains in the Southern Appalachian Mountains derive their name from the blue haze one sees over them, the visual effect caused by the millions of tons of water being transpired from all the leaves of the trees on a summer day (Welch, 2002).

[vi] (Malakoff, 1998; Vance, 2001; Ferber, 2004; Sverdrup et al, 2005).

[vii] (Welch, 2002).

[x] Bouillenne (1962).

[xi] Fallows (2011).

Ehrlich (1968:xi).

[xiii] For example, Eckmann and Ruelle (1985), IPCC (2014).