I think you may be confusing 'rationality' with 'positivism' or 'positive humanism' (or, what we in the supposed 'romantic' camp might term, the 'myth of progress'). These aren't the same, thus, the dichotomy built around 'romantics vs rationalists' is neither fair nor valid.

Many of us in the 'romantic' camp are no less pragmatic or empirical than the so-called 'rationalists'. Rather, we've seen the 'myth of progress' for what it is and gone beyond it by realizing that its fate applied to the human endeavor is entirely tied towards humanity's misguided 'perspective'. Such is often stated (rather crudely) as "we can't expect the tools that got us into this mess in the first place to offer the solution".

As an example, do I believe that humanity has the capacity to weather this 'technological adolescence' (to borrow a phrase from Sagan) and overcome the host of ecological disorders we've unleashed in the wake of the Industrial Revolution? Sure, it completely within the realm of logic to believe this possibility exists (anything's possible, even the Flying Spaghetti Monster). Do I believe that there's a reasonable probability that this will actually occur? Absolutely not! We're so far from the solutions and going farther each day that I have far less than a 5% certainty that positivism will ultimately be realized in reality. Is this non-rational or anti-rational? Of course not.

Those who subscribe to the 'myth of progress' don't do so because they have empirical or rational arguments to support the myth. They do so because the alternative seem unthinkable to them. Social and Environmental collapse are not something we're ready to deal with psychologically. But is there any real reason (other than faith) to believe the positivists? Even post the 60's 'environmental enlightenment', has humanity even come close to earning such esteem? Hardy. From a truly 'rationalist' perspective, do we have more reason to believe that (a) humanity will come through with completely new ideas and technology to work in harmony with nature and undue the damage we've done before it's too late or (b) continue on roughly the same course with periodic tiny fits and starts towards a balanced ecology while on the whole continuing to move ever desperately farther from such? If you subscribe to point (a), the overwhelming responsibility is upon you to provide evidence for such an optimistic perspective given an objective view of history. Point (b) is much more logically defensible by anyone with their eyes open.

There are plenty of 'rational' reasons to reject positive humanism as overly optimistic. It's much more than logically justifiable (truely rational) to remain skeptical about the myth of progress's reliance upon continued 'development' as the solution. Such conclusions need not be 'spiritual' nor 'back-to-the-trees', but rather presents themselves as a more truly 'rational' evaluation.

So the 'split' within the movement really boils down to hope. Some 'greens' hope that humanity mostly in its current form will make it through to a new level of civilization. These are your 'rationalists' (though, as argued above, are anything but). Others believe that the antidote to the destruction brought about by 'progress' is voluntary 'regress'. Less is more, lower levels of complexity are more resiliant, these kinds of premises. Our 'hope' in the continuation of humanity follows logically from where it's been before (the best kind of empiricism). We ARE able to create sustainable communities at the small scale. We have plenty of history of that. Large cities and complex interconnections, not so much.

This line of thought is interesting but I think it's kind of defeatist. OK, you are skeptical of or reject myth of progress's reliance upon continued development. Maybe you're right that a voluntary regress will make things better, but what are you going to do when the asteroid shows up or the super-volcano goes off or a nearby star goes supernova? We have a finite amount of time -- maybe 10 years, maybe 100 years, 10,000 years, but a just a snap of the fingers, really -- to get smart enough to spread and survive in the universe. Progress might be the end of use, but regress is sure to be.

While I understand your perspective, the concepts of 'defeatist' and 'end of use' are based on nothing less than one's idea of the meaning of human existence. We both believe our social order has the opportunity to evolve towards a 'better' state of existence for humanity. It's just a difference of opinion about what that 'better' state is. Is it longevity as a species on this planet? The ability to to carry ourselves into space to populate the far reaches of the galaxies (as Hawking seems to advocate)? Perhaps merely the luxury of sitting back to sip one's homemade brew from hops grown in the backyard and never seeing a gasoline-powered piece of equipment again? What ultimately is the point of 'spreading and surviving' anyway? I sure don't know, and I've yet to meet anyone who really does either. :-)

Sorry, meant to say "end of us", not "end of use".

Here is my attempt to answer your final question about the ultimate point of 'spreading and surviving'. If given the option to push a button that would undo my existence, I would not push it. Would you? I'm glad that I've had the chance to be alive. My assumption is that most people, even some who at some point in their life attempt to end their existence (suicide), wouldn't choose total nonexistence.

We're currently in a very fragile position -- single planet, might not be able to deflect a comet, ect. -- but we're getting smarter and more competent, and the pace of this growth is increasing. Once we spread over a large enough area, the number of future people who will have a chance to be alive goes to near infinity.

Once we're past the bottleneck we're in now everyone can do as they please -- whether that's farming or or industry or whatever -- and take their chances. However, we don't have that luxury. If we choose not to progress now, humans will die out sometime in the near future*, and we'll have deprived all of those infinite number of future people a chance to be alive.

So, yes, I agree with you that the 'better' state will be different for different people. Yes, car commutes and fluorescent office lights and many other parts of modern life are not fun. But we have to do it. It sucks, but we drew the short straw. Sometime in the future we'll reach a place where there is little chance that picking a certain 'better' state of existence that won't mean depriving all of future humanity of the chance to make their own choice.

Anyway, that's my two cents. Hopefully you can now say you have meet someone who has an answer to your question. ;-)

BTW, if you do really want to never see a gasoline-powered piece of equipment again have you thought of joining the Amish? That might work out pretty well.

* Out of context that makes me sound like one of those crazy people on the street wearing a sandwich board. I mean near future as in some finite amount of time that is extremely short in the universal time frame. 5,000 years? 20,000 years? 100,000 years? Who knows, but it will happen if we don't get any smarter than we are now.

Equating rationalism with positivism is a rhetorical trick, and not a very neat or honest one at that. I do not even recognize the useage you apply to the term "positivism" - it does call to mind "logical positivism" and August Compte - and those are clearly not associated with reason or particularily rational.

Same goes for your equating of rational empiricism (which has little or nothing to do with logical positivism) with what you call the "myth of progress". Any "rational" person with a reasonably experience based knowledge of human history, or of the natural world, knows that cultural progress is a delicate and insubstantial thing, capable of being destroyed or destroying itself through any number of things - but especially war, superstition, and the exhaustion of resources.

Reason (rational thought) is a useful tool in solving problems, including the problems caused by human activities and human created modes of social organization and resource use and misuse. While it is entirely possible, even likely, that sharp reductions in resource useage and purposeful reductions in our impact on the natural world would result in a net increase in the welfare of the earth and its creatures, including primates such as Genus Homo sp. sapiens, it is unlikely that "spiritually" based appeals for returns to simpler lifestyles will find the best way to accomplish such changes, or demonstrate that those changes do in fact offer the best way out of our current predicament, or persuade those who hold the pseudo-religious superstition that human society is progressing toward some desirable or desired end-point of the folly of their belief system.