Another telling of history highlights overthrowing tyrants, expelling colonizers, and, by marshaling the strength of numbers, progressively emancipating ourselves from slavery, poverty, and other degradations.

The key to deciding which of these perspectives is predictive of the human future lies in a paradoxical property of power. Once it's understood that a group's competitive success vis à vis other groups depends on limiting abuses of power within the group, King's optimism regarding the curvature of the moral arc of history is vindicated.

Here's the gist of the argument: If a ruler is regarded as unjust or self-aggrandizing by his subjects, morale will deteriorate to the point that group solidarity is weakened and the will to defend the group is impaired. Unjust leaders neither deserve nor elicit loyalty and, when push comes to shove, their people turn on them.

This means that governance that promotes loyalty and solidarity has survival value. Even societies that adopt a predatory stance looking outwards, are short-sighted if they disregard dignitarian values looking inwards. Over the course of history, not to complement outward-directed predatory capability with a modicum of dignity for those within the group has been to lose out to groups whose stronger social bond enabled them to marshal and project superior force.

For this reason, upholding dignity is more than an admonition to be "nice." A policy of relatively equal dignity enhances the power of groups that practice it. None do so consistently, of course, but some do so more than others, and this gives them a competitive advantage stemming from social cohesiveness. This suggests that, on a millennial time scale, the golden rule is self-enforcing. We were too quick to judge it toothless. Rather, it simply took a few thousand years to cut teeth.

As we realize that over the long haul dignitarian societies have a competitive advantage, and as less dignitarian groups are absorbed by more dignitarian ones, we gradually operationalize the golden rule and extend its writ.

It's important to recognize that within groups, it's not just "top dogs" who abuse power. Power abuse is a tempting strategy at any rank because everybody is a somebody to someone and a nobody to someone else. Accordingly, unless you're at the very bottom, a predatory posture can be assumed towards underlings no matter where one stands in a hierarchy. And, even if you are at the bottom, you can always kick the dog. Much cruelty to animals is a result of indignation that humans feel towards other humans who have humiliated them, but whom they dare not confront because the abusers are shielded by the power attached to their rank.

Because societies predicated on equal dignity are more productive and creative, and are more strongly committed to their common cause--be it aggressive or defensive--they are, on average, fitter. This does not mean that dignitarian groups win every contest with more predatory groups. Factors other than social cohesion also figure in the outcome. But it does mean that, with starts and fits, organizations and states that tolerate power abuses effectively de-select themselves. Over a long enough time period, the circle of dignity expands.

The paradox of power is that, statistically, dignitarian societies gradually absorb less dignitarian ones until finally there is no longer a significant likelihood of inter-group predation. Disgruntled outliers may resort to violence or disruption, but they will not be successful unless they are serving as proxies for a larger group that shares their grievances and their indignation.

A selection process governed by the same dynamic unfolds among organizations. For example, more dignitarian companies will, on average, serve their customers and employees better, and will outperform less dignitarian ones. In a phrase, dignity works, indignity doesn't.

While the evolutionary trend prophesied by Martin Luther King Jr. may at first sound like wishful thinking, it is revealed as a logical consequence of the free play of power within and among competing groups. The paradox of power--that in the long run, right makes might, not vice versa--provides causal underpinning for optimism regarding the curvature of the moral universe. Despite the relentless drumbeat of bad news, the twenty-first century could witness the gradual phasing out of our age-old predatory strategy and the adoption of a dignitarian one. Even if there are major setbacks--and we must expect reversals and prepare for them--there is reason to believe that the state toward which humankind is tending is one of universal dignity.

Is Competition Compatible with Dignity for All?

There's a conceptual barrier to putting our predatory past behind us, and not to address it would be remiss in a series of articles claiming there is reason to hope.

Disallowing predation sounds utopian to many because, as a society, we haven't quite figured out how to forego habitual predatory behavior without inhibiting competition. Although it's natural to see competition as the culprit (because it is so very often unfair, and because many competitors interpret winning a particular competition as an excuse for demeaning and exploiting those who lose), no society that has curtailed competition has long endured. As libertarian ideology confuses predation with competition and may find itself an apologist for the former, so egalitarian ideology confuses competition with predation and may advocate killing the goose--competition--that lays the golden egg. To this dilemma--how to allow competition while disallowing predation--dignitarian ethics provides a possible solution.

Competition is an integral part of our past and fair competition is indispensable to a prosperous, robust future. To delegitimize gradations of power is not only impossible, it's a recipe for dysfunction. Fair competition is in fact one of the best safeguards against rankism ever devised.

From the natural selection that drives the differentiation of species to the marketplace that refines products and ideas, competition determines fitness and protects us from abuses of power by economic and political monopolies. To abolish competition is to invite stagnation, and eventually to fall behind societies that hone their competitive edge.

The difference between predation and competition is that predation knows no rules. In contrast, competition can be made fair. In athletic contests, we do this by having referees to enforce the rules evenhandedly. Making sure that competition is fair--by disallowing rankism in all its guises--is a proper function of government.

At every point in our social evolution, power rules. Power is neither good nor bad, it just is, and trying to eliminate power differences is barking up the wrong tree. Abuses of power, however, are something else. They will persist only so long as the individuals or institutions perpetrating them wield greater power. This would be grounds for cynicism were it not that when power is abused there eventually surfaces a less abusive and therefore ultimately more powerful alternative.

Groups that harbor indignity burden themselves with the corrosive effects of suppressed indignation. The long-term trend of this evolutionary process is the discovery of ever more effective forms of cooperation, successively out-producing, out-performing, and finally replacing more rankist organizations, institutions, societies, and states.

Dr. King's intuition regarding the curvature of the moral universe is correct: it bends toward justice.