Monday, April 30, 2007

Limits to Murder

The maximum violent crime rate of 1,299 per 100,000 people per year predicted in my stress model can be explained easily as the maximum average number of people per year over a lifetime (100,000 people divided by 77 years per lifetime). At this rate, every person in a fixed population would eventually be a victim of violent crime.

Interestingly, the predicted maximum murder rate is 17 per 100,000 per year. This is equal to the maximum violent crime rate divided by the number of years in a lifetime (77). It is as if the violent crimes in a single year were instead murders, and distributed evenly over a lifetime.

Worldwide, the average number of murders per year (over a lifetime) should not exceed the size of the population divided by the square of the average life expectancy in years. A good test of the model would be to find out if the number of people killed in wars and crime exceeds this amount (I think it’s reasonable to consider casualties of war as victims of murder). Since violent crime is more difficult to measure than casualties, the number of worldwide murders could be used as an indicator of global stress.

Saturday, April 28, 2007


In an attempt to test my stress model, I studied Colorado crime rates. I immediately noticed that violent crime rates dipped below the minimum limit predicted by the model, appearing to disprove my most basic assumption: that people in the outer edges of a population (and presumably under the most stress) were responsible for violent crime.

The close parallel between murder rates and average stress suggested that violent crime might behave the same way. I revamped the model, this time based on the premise that violent crime is proportional to average stress. The proportionality factor became immediately obvious: Normalized stress (average stress as a fraction of the maximum possible average stress) is the per capita violent crime rate multiplied by the number of years in an average lifetime. While my basic conclusions are left unchanged, the new model allows any violent crime rate between zero and 1,299 (per 100 thousand people per year).

Of practical concern is the huge question of what real-world variables correspond to “adjusted power” that can be measured and manipulated in a quantifiable way.

Friday, April 27, 2007

Stress and Murder

I’ve been unable to verify that there is a stress limit for the murder rate similar to the one I’ve assumed for the violent crime crate. I finally curve-fitted the murder rate to the violent crime rate, and found that the murder rate tracks very closely to the average stress in the population. Both never get below about 45 percent of their peak values.

The stress model predicts that while the violent crime rate will never drop below 374 (crimes per 100 thousand people per year), the murder rate will never drop below five. The model also predicts that the maximum violent crime rate is 839 and the maximum murder rate is 11.

With three-quarters of all murders (including non-negligent homicide) involving firearms, it is conceivable that the maximum murder rate might drop to a fourth of its present value if we remove the chance someone will use a firearm to commit murder. The minimum rate would still be 44 percent of the maximum, or about one.

As Michael Moore’s movie “Bowling for Columbine” demonstrated, other countries have achieved murder rates comparable to the minimum. My model indicates how this could happen: Reduce the stress on the population by both maximizing the power that everyone has over their lives and training them to accurately perceive the world. The latter approach (addressing the “intelligence” part of the model, or “adjusted power” between zero and its half-way point) could include demonstrating that murder is not a “positive” tactic for reducing stress.

Thursday, April 26, 2007

Stress and Consumption

I further refined my stress model, adding the measurement of total “distance” traveled by the population. (For a graph of this and other variables over time, see my Web site.)

I’m hoping to correlate distance to energy use, and thereby consumption, thus tying this model to my consumption model. Annual values of distance (compensated for population size) are not correlated with U.S. energy use, but a plot of cumulative distance versus cumulative energy use looks well behaved; though most attempts at reasonable curve fits show energy climbing at an increasing rate as cumulative distance increases. This implies that we would need to reduce our annual per capita distance traveled much lower than my model implies is possible (that is, below 33 percent of the maximum) to level off our consumption with our current energy portfolio.

Wednesday, April 25, 2007

Stress and History

After some further analysis, I determined a formula for a population’s average stress as a function of violent crime rate, which turned out to be parabolic (a second order polynomial). What I’ve been calling “power” (combining both increases in the minimum, and decreases in the maximum) is also a parabolic function of the violent crime rate. Reviewing the historical record of violent crime rates, I was able to construct a new view of the past 30 years.

From 1975 to 1980, stress increased while minimum power decreased. From 198o until 1985, the stress declined slightly and minimum power increased. From 1985 until 1990, stress increased dramatically, corresponding to a similar decrease in minimum power. During the following two years, with minimum power as low as it could get, maximum power decreased. In 1991, both stress and power leveled out. From 1991 until 1995, stress declined while maximum power increased to its 1990 level. From 1990 until 2000, stress decreased (as fast as it had increased before 1991) to roughly its 1985 level while minimum power increased. Stress and power began leveling out through 2005.

Tuesday, April 24, 2007

Theoretical Stress

In a simulated population of 1,000 people whose “comfort zones” are distributed randomly between values of 1 and 5, starting from “positions” also randomly distributed in that range, each member will experience a “stress” defined as the distance between where they are and where they want to be (their comfort zone). This stress will motivate them to move closer to their comfort zones, but they will be restricted by two variables: “power” or the fraction of the distance they can practically cover in their lifetimes; and “intelligence,” their perceptions of the directions and distances to their targets. Power and intelligence determine the distances (and directions) that people travel.

In this theoretical model, each member of the population has a random value of power and intelligence that lies between specified minimum and maximum values. By varying the ranges of power and intelligence, we can see what effect they have on the distribution of stress throughout the population at the end of an interval of time (the lifetime of a person).

For the full range of power and intelligence (zero to one for power, and minus one to positive one for intelligence), the average final stress is 1.3 and the standard deviation (a measure of the width of the “bell curve”) is 1.0. There is 47 percent of the population within 1.0 unit of the average, and 53 percent of the population with stress from 1.0 to 4.0. For no range of power or intelligence (both equal zero), the average stress is still about 1.3, the standard deviation is 0.9, and the fraction of stressed people (those with stress of at least 1.0) increases to 56 percent.

Restricting intelligence to positive values, from zero to one (people work toward reaching their comfort zones, instead of moving away from them) reduces the average stress of the population from 1.3 to 1.0; and reduces the fraction of stressed people from 53 to 42 percent. If, after this, the minimum power is adjusted upward, the average stress decreases linearly with power to a value of two-thirds (about 0.7) at total power (power equals one). Note that varying power in this way is mathematically equivalent to keeping the range of power between zero and one, and varying the minimum intelligence.

If, as it appears, the violent crime rate is proportional to the fraction of stressed people (divide the number of such people in a population of 100,000 by the number of years in a lifetime, currently about 77), then this theoretical exercise implies that to reduce crime we should decrease the overall stress on the population by increasing people’s abilities and training them to perceive the world accurately.

Monday, April 23, 2007

Stress and Security

If the amount of violence is proportional to the fraction of a population that is under high stress, then three security strategies become obvious: removing the stressed people from the population, reducing stress on the people who are experiencing most of it, and reducing the stress on the entire population.

The most humane way to remove the stressed people corresponds to what I earlier called “isolation” (the flip-side, separating the population from the stressed people, is what I called “retreat”). The most inhumane way to do this is what I called “offense,” with “defense” somewhere in-between. Reducing the stress on the stressed people corresponds to what I called “alliance.” Reducing stress on the entire population is a critical requirement for what I referred to as “assimilation.” It should be noted that a trivial but historically viable alternative to “removing” stressed people is to keep populations artificially small (less than 250), so that statistically (under most conditions) the number of murderers is less than one.

Offense, defense, isolation and retreat can now be analytically shown to be the most inadequate solutions to the problem of violence. They simply delay the onset of violence until either conditions become more stressful or another generation is born, members of which having a low tolerance for the existing stress.

Reducing stress on individuals is only slightly better, requiring a complex social structure that must shift with conditions and necessarily increase stress on other members of the population (who must interact directly with the affected people). It is the fallback position when the stress on the entire population cannot be effectively reduced.

Sunday, April 22, 2007

Stress and Violent Crime

If there is a constant fraction of any random population predisposed to commit violent crime, then something in their environment must trigger increases and decreases in the number of crimes they commit. Suppose that everyone feels most comfortable when their environment serves their personality; for example, social people favor environments with a lot of people around, and incurious people favor simple (as opposed to complex) environments. They will be most stressed when their environments vary from these “comfort zones,” and they will tend to take whatever action they can to reduce that stress: they will either find other environments or change the ones they are in.

People at extreme ends of the personality spectrum will be under more stress than others in environments that favor the average, and particularly stressed in environments that favor the other extremes. If, as psychological studies have suggested, other people are the source of the most stress in our environments, then if highly stressed people have no power to either leave or change their environments then they may resort to hurting other people: that is, committing violent crimes.

Matching arrest rates to crime rates (as fractions of a population over expected lifetimes), the data from 1975 to 2003 indicates that in a population of 1,000 people there will be 135 violent criminals and four murderers. In terms of stress, measured as variation from one’s comfort zone, my behavior model suggests that this statistically corresponds to about two standard deviations for all violent crime and three standard deviations for murder. Put another way, if the range of personalities is measured on a scale of one to five, then people more than one of these units away from their comfort zone will be stressed out enough to commit violent crime, while someone more than 1.5 units away from their comfort zone could commit murder.

Saturday, April 21, 2007

Varying Crime Rates

If my “bad quarter” hypothesis is correct, that one-fourth of a population will commit violent crime over a lifetime, then either the violent crime rate would vary randomly around an average value (adjusted for life expectancy), or the number of crimes per criminal would need to change to compensate for the observed change in crime rate.

The crime rate has not varied randomly over time. From 1980 to 2003, the U.S. violent crime rate appeared to drop linearly over time except for a “bump” in the 1990s. The lifetime rate (percent of the population who will be a victim of violent crime over a lifetime) dropped from 44 (in 1980) to 42 (in 1985), then climbed to a peak of 57 in 1991 and gradually dropped to 40 by 1999 before resuming its earlier trend downward, reaching 37 in 2003. The rate for murder and non-negligent manslaughter paralleled that for violent crime; as a percentage of violent crime it actually dropped (from 1.7 percent in 1980) from and appeared to start leveling off (at 1.2 percent by 2003).

The ratio of violent crimes to arrests for violent crime dropped precipitously from 1993 to 2002, from 4.3 to 2.3. The bad quarter hypothesis projects those ratios to be 2.3 and 1.4, implying that roughly half of perpetrators have not been caught.

Friday, April 20, 2007

Bad Quarter

It is either an eerie coincidence or an important insight from recent violent crime statistics extrapolated to a lifetime (based on average life expectancy) that from one-sixth to one-third of the population will perpetrate violent crime. This is based on the assessment that 36 percent of Americans will be victimized by a criminal committing either the first or second crime. The average is close to one-quarter, which is the fraction I expect based on random personality profiles. The fraction of (six) security options corresponding to violence is also close to this number (offense, which is purely violent, and the half of defense that doesn’t include attempting to destroy the attacker). Also interesting is the fact that one percent of violent crime involves death; suggesting that the same fraction of the “bad quarter,” or one person in 400, is a deadly threat to the rest of us.

Assuming we can profile people sufficiently to assess whether or not they are likely to threaten us with violence and death, what actions are appropriate? As I’ve pointed out elsewhere, I believe that objectifying people is an important step toward taking evil actions (judging that the actions, not the people, are inherently evil), and should be avoided as much as possible. We must hold people accountable for what they actually do, not what they may likely do. The subtle wrinkle I’d like to add here is that objectifying is helpful and perhaps even necessary in creating the tools we might need to deal with a threat, but individual behavior must be the trigger for using those tools.

Thursday, April 19, 2007

Violence and Guns

In the U.S., the violent crime rate is about 80 times the crime rate for murder and non-negligent manslaughter (about three-quarters of the lower rate involves the use of firearms). Over a lifetime, out of 1,000 Americans 361 will be victimized by violent crime in their lifetimes, with four the victim of murder or non-negligent manslaughter (three of whom dying from the homicidal use of firearms) and 328 the victims of other violent crime that does not involve firearms. An additional eight people will die from other uses of firearms (that is, a total of 12 will die from use of firearms).

In terms of perpetrators, the number of people arrested for violent crime is less than half the number violent crimes (this is consistent for crimes involving death). This implies that either half have not been caught, or there are two crimes per criminal. By comparison, about one in five people own enough firearms to arm over two-thirds of the population, and each firearm can kill many, many people.

These statistics highlight the ambiguity of the gun control issue. If we want to reduce violent crime, then firearms are a small part of the problem. If we want to reduce crime that results in death, then firearms are a large part of the problem; they are, as I’ve said, weapons of mass destruction.

Wednesday, April 18, 2007


Of the security approaches used by law enforcement, the most humane and effective are a combination of containment and assimilation. A recent “60 Minutes” segment described how education for prisoners improved psychological health and indicated that it dramatically reduces recidivism. This matches the results of my own statistical population modeling, where having the most people with accurate knowledge of the actions required to reach their personal comfort zones minimizes the average stress of the population. Containment during education (which, by the way, we practice with our kids by sticking them in school) protects society while ignorance and lack of understanding are too low for people to make rational decisions.

Another form of containment, through the limiting of weapons of mass destruction, is useful in the general population to the extent that dangerous ignorance is present in statistically significant numbers of people. I define weapons of mass destruction (WMD) as anything that can kill more than the number of people who could be expected to pose a direct, deadly threat to an individual. The most generous interpretation of deadly crime statistics (all people arrested are guilty) is that annually there are five attackers and six victims per 100 thousand people in the United States. As long as the government is under the people’s control and maintains both a police force and a standing military (for dealing with other threats), there is no reason why any of us should have the means to kill anyone in a lifetime.

Tuesday, April 17, 2007

Threats from Individuals

Groups attempting to grow in membership and power promote evil by treating members of other groups as objects rather than people. The same can be said for individuals, exemplified by mass shootings such as the recent one at Virginia Tech.

When one person kills a group of strangers, the killer has objectified the victims: they represent a set of characteristics that the killer feels must be destroyed. The victims are perceived as either a threat, or an obstacle to what the killer believes is good.

The security of potential victims depends on identifying those who perceive them in these ways, and then applying the most practical and appropriate security approach or approaches (offense, defense, containment, alliance, assimilation, or retreat). Western societies like the United States typically apply defense (use of force by police), containment (prison, weapons controls) and assimilation (education) to minimize the threat from individuals. Only a few societies, considered barbaric by the rest the world, also use offense (the death penalty). Few others will use alliance (such as corruption and the support of terrorist organizations). Retreat, or surrender, is seldom an option.

Monday, April 16, 2007

Order and Disorder

Physics teaches us that in any closed system, entropy, or disorder, will always increase. Put another way, groups will gradually become indistinguishable from each other, given enough time. They will grow, interact, and merge, with individual behavior becoming more random.

As beings who value order, this fate is unacceptable. There are two ways humanity has dealt with this problem. One way corresponds to the retreat option in attaining security: Exploring regions untouched by people, or effectively “opening” the system (available habitat). The other way limits the size of the population so that more of the system is available to those who survive.

In practical terms, “opening the system” would involve exploring and settling other planets. This is the most humane approach, effectively postponing the inevitable encounter with the ultimate limit to growth: our inability to reach new resources fast enough.

The alternative may be a series of paroxysms of growth and death as the population reaches a maximum, declines to a level where people are able to express their uniqueness and rises again.

Sunday, April 15, 2007

Respect and Security

How can we maintain security and respect at the same time? Only one of the six security approaches is fully respectful of both the threatened group and the threatening group: alliance. In an alliance, each group maintains its integrity while cooperating toward common ends. The alternatives, however, alter one or both groups either structurally or in their ability to function.

Statistically, only one-sixth of a random population is likely to support any particular option, which may be a major reason why we often see combinations of one or more applied in reality, varying in relative weight over time. Another major reason may be the fact that every group has commonalities with each other, such as the fact that we are genetically nearly identical, which calls into question the whole notion of the groups being “well-defined,” that is, sufficiently different from one another. If the traits that differentiate groups can be altered, such as religion and political affiliation, then given sufficient contact and time there may be diffusion between the groups – mutual assimilation.

This discussion begs another question: Why would one group threaten another in the first place? If by default or reason the members of one group have a set of shared traits that identify them as different from another group, and those traits are immutable over a period of time, the members may be acting on the common urge to grow. Growth often involves the acquisition of more members and the resources to support them. Unfortunately for all groups, growth by definition is unsustainable, and the groups that survive the longest learn to live with this fact by constantly seeking an optimum size for their typically changing environment. When one group’s “environment” includes the members of another group (as it must in any closed system, limited by resources or speed of acquisition of those resources), then it must limit its growth, alter its own characteristics, or attempt to overcome the other group (threaten it).

Saturday, April 14, 2007


One of the great controversies of this or any other era is how to maintain effective security. Loosely speaking, there are at least six approaches: offense, defense, containment, alliance, assimilation, and retreat. Each of these approaches presumes a well-defined group whose survival, livelihood, or cultural integrity is threatened by another well-defined group.

Offense involves attacking (destroying) someone perceived as a threat, while defense involves neutralizing an attack. Containment is the isolation of the threatening group, disabling its ability to attack. Alliance is the defusing of a threat by finding common ground with the attackers where both groups benefit. Assimilation is an extreme version of an alliance: two groups merge to form one new group. Retreat is the avoidance of an attacking group, usually by physical separation.

Depending on the groups (or more specifically, the personalities of their leaders) and the practicality of each option, one or more security approaches may be more likely to be tried than the others. I would expect offense or retreat to be favored equally by people on one side of the personality spectrum, with the rest of the options favored by those on the other side of the spectrum.

Based on this analysis, it should be no surprise that half of any randomly distributed population would think of security in terms of attack or retreat, while the other half thinks in terms of “accommodation” in one form or another.

Friday, April 13, 2007


The cover story for the May-June edition of Mother Jones magazine reads “In 93 years, half of all life on Earth will be extinct. So what?” The estimate is based on calculations by esteemed biologist E.O. Wilson.

I used my consumption model to determine under what conditions the prediction would be true (and to further test the model). The result was jaw-dropping, after I fixed the feature that is supposed to reduce consumption by a fixed amount the first year after changes start. According to my model, the Living Planet Index (which measures the average population sizes of all species) falls to 48 percent of its 2006 value in 2100 if next year the global footprint drops to less than one percent of its current value and then resumes its three percent annual growth until at least 2100. That is, my model suggests that Wilson’s prediction is based on current annual consumption that is less than one percent of its actual value. The model shows that starting with the actual consumption we could reach the half-way mark much sooner, by 2011.

Thursday, April 12, 2007


In my view, most of the world’s problems would be solvable if more people chose to respect other people, other species, and the way the Universe works.

We are much less likely to hurt those who we respect than those we don’t. Building empires by walking over other countries and their traditions is unthinkable if you respect their citizens and cultures. Destruction of “the environment” is less likely if you respect both the people and other species that inhabit your common home. Succeeding in creating a positive future demands accurate understanding and respect for how natural systems operate and evolve, minimizing unintended consequences of our actions.

Racism, genocide, wars, and catastrophic climate change could be avoided if we all took the time to appreciate the value of our shared heritage and respected each other enough to develop a common vision of the kind of world that ALL of us, including future generations, could live in.

Wednesday, April 11, 2007

Racism in the News

Radio host Don Imus made headlines recently with an off-the-cuff remark about a college basketball team which showed a lack of respect, or hatred for, both African Americans and women. The remark was a classic example of what I have called “the root of all evil.”

Racism and misogyny first objectify people by treating individuals of each group as identical instances of an “object,” and then assign a negative emotional response to the imaginary objects. The peril, which many in our society are rightly reacting to, is that the talk show host’s listeners (or other talk show hosts) might emulate Imus and that the emotional response might be followed by negative action (commission of evil acts).

Unfortunately, as the saying goes, that ship has already sailed. Several right-wing radio and television hosts such as Rush Limbaugh have openly promoted hatred of women, ethnic groups, and homosexuals, but with no comparable public outrage. That Don Imus is raising such a stir now may be due to his more mainstream reputation: the others are already marginalized, appealing to a known base of listeners who welcome hate talk while everyone else writes them off. Imus now faces this same marginalization, because society can’t allow his behavior to be legitimized for the rest of the media.

Tuesday, April 10, 2007


The key feature of my consumption model is the strong correlation between consumption and population, where “consumption” is defined as the total mass processed by humans. I’ve assumed that the mass consumed per year is proportional to the global ecological footprint as measured by the World Wildlife Fund (WWF), which has increased exponentially over time. Population as a function of consumption appears to be a downward facing parabola: that is, it rises to a peak and then drops off at the same rate. The rapid rise of consumption results in a faster approach to the population peak and the other side of the consumption-population curve, thus appearing as a population crash.

This mathematical description, if accurate, explains the “what,” but not the “how” or “why” behind it. If converting mass in the environment can yield more people, how can converting more mass yield less people? The simplest explanation I can think of is the analogy of someone generating a lot of waste in the process of building a house, growing food, and so on, but eventually overwhelming the trash collectors who haul the toxic waste away and reprocess it. Eventually the waste overwhelms the people as well.

Conservation biologists have a list of factors they use to explain how the populations of other species are lowered by human activity, which is summarized by the acronym HIPPO: Loss of habitat (“H”), introduction of invasive species (“I”), pollution (“P”), human population (the second “P”), and hunting or over-harvesting (“O”). All of these factors are no doubt behind the other correlation I found, between increasing consumption and a decreasing Living Planet Index, which indicates the size of the populations of other species. HIPPO may also help explain how our own population is poised to drop.

No matter how far we attempt to distance our fate from a reliance on Nature, humans are still dependent on other species for a wide range of services, not the least of which include cleaning the air and water, and providing and processing food. As other species die off, they can no longer provide those services. Without their services, we must pick up the slack, and our technology is not quite up to the task.

But HIPPO may have more direct effects on us, especially (as I’ve indicated) through pollution. Toxins that poison us or cause or exacerbate diseases such as cancer, and carbon dioxide emissions that change the climate (which adversely affects food production, introduces invasive disease-bearing species to environments ill-equipped to deal with them, as well as increasing the intensity of storms and droughts) are perhaps the most significant ways that pollution can reduce the human population. Over-harvesting may also play a role, in the form of more wars and violence, which could be traced to increased stress as members of our population interfere with each other’s lives more and more, while competing for fewer resources (loss of habitat).

Saturday, April 7, 2007

Not in My Name

This week the Pentagon released a report verifying what most people had suspected about the run-up to the Iraq war: that the Bush administration cherry-picked information from unreliable sources, contradicting the judgment of the professional intelligence community that Saddam Hussein had no active involvement with al-Qaeda. Basically, the American people and the world were lied to, and yes, it was intentional. At practically the same time the report was released, Dick Cheney was continuing the lie, and his boss was making erroneous speeches tying the war to 9/11.

I happened to be reading Chalmers Johnson’s recent book about American imperialism, Nemesis: the Last Days of the American Republic, after seeing him promote the book on C-SPAN. In the book, Johnson lays out a well argued and detailed case that since World War II the United States has become the world’s latest empire, spanning the globe with military presence, with presidents using increasing amounts of “dark” assets to influence foreign governments and now our own. Without exception, our attempts to force other countries to go our way (with almost no oversight by the American people) have been dismal failures. The Iraq war is just the latest and perhaps most egregious example of this. Johnson argues that we have two options to choose from, based on models from the past: the course of Rome, which sacrificed its republic by trying to maintain its far-flung empire, or the course of Britain, which sacrificed its empire to maintain its republic. Recent events seem to have us following Rome’s example.

Even more than usual, I was boiling mad at my country’s leaders. That they lied to me was one thing, but their motives were not even good ones. They are committing the worst acts of evil in my name, and I give a damn about my legacy. To add insult to injury, the Bush administration reacted predictably to the latest report by the United Nations panel on global climate change, arguing that the problem needs more study, and other countries must commit to action before we do anything to deal with global warming. My latest consumption model projects that Al Gore’s plan to reduce carbon emissions by 2050, if enacted worldwide, would postpone the crash of the human species by 100 years (from 2047 to 2147), which could buy enough time to reverse our destruction of the Earth. To resist even this modest approach is criminal, but our leaders don’t want to preserve the future; they want to exploit the present.

Efficiency Revisions

For various reasons, I had set the maximum year measured by my consumption model at 3814, some 1807 years in the future. I decided to reset that maximum year to 4007, or 2000 years in the future, and re-run my efficiency numbers. Based on this change, while the current conditions would still result in a species population crash in 2014 and a human population crash in 2047, the minimum efficiency factors needed to avoid human casualties and loss of other species increased somewhat. Specifically, to keep from losing human population within 2000 years, we will need to increase our efficiency of consumption (or reduce consumption altogether) by a factor of 124 (if done in five years) to 258 (if done in 50 years). To keep from losing other species, the range is 281 to 1662 for the same time spans.

If we don’t meet the efficiency target for no human population loss, the model can project what our casualties will be for various efficiency factors achieved exponentially over a given time span. For example, if we exponentially increase our efficiency for the next 30 years, we will lose everyone if we multiply our efficiency by less than 30 over that period, and we will have no casualties if we multiply our efficiency by at least 182. Between those two values, the casualties decrease exponentially as efficiency increases. An efficiency factor of 50 results in 1.9 billion casualties (27 percent of peak). An efficiency factor of 100 results in 168 million casualties (two percent of peak).

Thursday, April 5, 2007


I revamped my consumption model to take account of ecological footprint going back over 500 years, and was able to closely predict population growth over that period. Looking ahead, it pushed out by 20 years the amount of time we have before our population crashes. My goal was to reliably estimate the time in history when we each used the amount of resources we must use in the future to avoid losses in our population and the crash of other species’ populations. The answer, depending on how long the world reduces the annual rate of consumption before settling at a fixed amount of consumption per year, is some 300 years ago, at the start of the Industrial Revolution.

Put another way, the world must increase its efficiency of per capita resource use by a factor of about 100 to keep our population from falling after it peaks, and by a factor of several hundred to keep other species’ populations from crashing. Interestingly, our (western) economy wastes roughly 100 pounds (in production and packaging) for every pound of product used (not counting externalities such as gas emissions and energy use during transportation), implying that we would need to extract only those resources that we actually use while cutting out the other costs.