In previous "third rail" posts, I've discussed the sustainability movement's reluctance to speak ill of its icons, the underlying despair of many sustainability activists, and the movement's capacity to self-destruct. In my fourth and final "third rails" post, I'll be addressing what is perhaps the most taboo topic of all—the possibility that there are hierarchical levels of consciousness, with people at higher levels more able to "get" sustainability.

Many people are offended by this notion, for understandable reasons. For one thing, it violates one of our most basic precepts. The Declaration of Independence declares: "We hold these truths to be self-evident, that all men are created equal …" The notion that people operate at different levels of psychological evolution seems to say something quite different.

On top of this, there is the much more recent politically correct hostility toward hierarchy and elitism in all its forms: male chauvinism, racism, sexism, and the rest of it.

The result is a cultural two-layer cake, with the Declaration of Independence's rich ode to equality topped by all that indignant PC icing. Together, these objections can cast a pall over any open discussion of the subject. Some years ago, I gave a lecture about levels of consciousness to a group of sustainability activists and practically had my head taken off. The subject is that fraught.

So what is this theory that people find so offensive, and is there any merit to it? A brief summary would go like this …

As individuals, we all evolve from one level of consciousness to another. Babies cannot perceive the world from others’ point of view, but older children can. It is a cultural and scientific given that children evolve through levels of psychological development.

Some people believe that the developmental process continues in adulthood, and that a culture’s values and institutions reflect how far up the ladder of consciousness its "middle of the bell curve" members have progressed. This is where things get controversial.

One representative model of psycho-spiritual growth, called Spiral Dynamics, proposes that adult consciousness ascends through two tiers, with the first having six levels and the second, two levels. For our purposes, the relevant ones start with the fourth level of the first tier, which is built around the concept of fidelity to a higher truth or principle. Fundamentalist religious believers operate at this level, according to this theory, as do super-patriots who believe in "my country right or wrong."

At the next level (Tier One, Level Five), prosperity is the central principle. This level is the axis of global free-market capitalism.

Tier One, Level Six is what we typically think of as green, with eco-communitarian values.

Everyone who is centered in the first tier is similar in this respect: they all believe that if everyone were operating at their level, things would be right in the world. The fundamentalists want everyone to be fundamentalist, the capitalists want everyone to be capitalist, and the greens want everyone to be green. The result is constant conflict.

The second tier is different. Here the emphasis is on appreciating the value of all the developmental levels and on pursuing goals that improve the quality of life for people at all levels on the Spiral. The "enemy" largely drops out of the equation.

Whatever its merits, it's a controversial model, with something to offend almost everyone. Even greens, who come out pretty well overall, don't have the satisfaction of knowing they're at the top of the pecking order, plus there are those problems with its being hierarchical. Only the second tier comes out unscathed, and they—so sayeth the theory—comprise a very small percentage of the population.

Any discussion of this nuanced topic would be incomplete without citing some of its redeeming aspects.

First, development inside a single individual isn't homogeneous. Different aspects of the self evolve at different speeds, and sometimes not at all.

Second, there is a spiritual component to theories like this. Spiral Dynamics is consistent with models of consciousness developed by yogis who were mapping the path of spiritual evolution.

Third, although there is an undeniably elitist aspect to the Spiral Dynamics model, unlike most types of elitism it's not exclusive. In fact, it's quite the opposite—the prevailing assumption is that the more people there are at higher levels, the better it is for everyone. Unlike social aristocracies, nowhere is there an intent to keep people "down" or "out."

Finally, Spiral Dynamics also has a distinctly un-elitist aspect. Do we look down at children because they have the consciousness of children? No. People are where they are in their journey up the Spiral; it's nothing to bear judgments about.

Whatever one's feelings about Spiral Dynamics, and the topic has more twists and turns than a mountain pass, its explanatory capacity is intriguing. It can help us understand, for instance, why many members of the green community feel they've reached a level of understanding that more mainstream members of society haven't attained. It's because they're at the highest level on the Tier One Spiral.

It also provides an interesting perspective on our political dynamics. It suggests that George W. Bush operates from the Level 4-5 range (fundamentalist/capitalist), while Bill Clinton is at the Level 5-6 range (capitalist/green). And Barack Obama? Well, the case can be made that he's a Tier-Two kind of guy. This would explain not only his genuinely post-partisan appeal, but also why he's so baffling to political progressives (Tier One, Level Six) who so badly want to claim him as one of their own.

Finally, Spiral Dynamics can help explain why sustainability has been slower to make inroads than one might expect, given the gravity of the crisis. A Spiral Dynamics analysis suggests that it's essentially a Level Six and higher phenomenon, in a world where our personal and political cultures have had their center of gravity in the Level 4-5 range.

It suggests other things as well, for instance, that our progress in achieving sustainability depends on how quickly this center of gravity reaches Level Six or higher, and that we must tailor our communications about sustainability to the level at which people are functioning.

Given how charged the subject is, it's understandable that we sweep the topic under the rug. We lose when we do so, however. Our integrity suffers when we let social and political considerations trump the pursuit of truth and understanding, and we lose something else besides. Models like Spiral Dynamics are analytical frameworks. Suppress them, and the strategic insights they produce are suppressed too.

Sustainability has exterior and interior aspects. Externally, it's about creating a just society and healthy planet. Internally, it's about the commitment to look the truth in the eye and take appropriate action. It's about learning and growing—about doing our level best to live in integrity with things as they really are.

When we duck important conversations, either by refusing to address them or by devolving into outrage when the subject does come up, we do ourselves and the world a disservice. And disservice isn't sustainable.