‘Sustainable’ doesn’t imply ‘stagnant.’
In The ‘Sustainability Solution’ to the Fermi Paradox (Journal of the British Interplanetary Society 62: 47-51), Haqq-Misra and Baum propose the following counterargument to the Fermi Paradox:
the absence of ETI observation can be explained by the possibility that exponential or other faster-growth is not a sustainable development pattern for intelligent civilizations. Exponential growth is implicit in Fermi’s claim that ETI could quickly expand through the galaxy, an assumption based on observations of human expansion on Earth. However, as we are now learning all too well, our exponential expansion frequently proves unsustainable as we reach the limits of available resources. Likewise, because all civilizations throughout the universe may have limited resources, it is possible that all civilizations face similar issues of sustainability. In other words, unsustainably growing civilizations may inevitably collapse. This possibility is the essence of the Sustainability Solution.
However, this argument fails to take into account the critical fact that the resource base available to a civilization as it expands in area or volume also expands. Just as nothing precludes a sustainable civilization expanding from a single geographical location to an entire planet, there is nothing to suggest that a sustainable civilization cannot expand from a single planet to the entire galaxy. In fact, if a mechanism like Von Neumann probes were used, the amount of resources dedicated to exploration would be bounded and independent of the final explored volume (in the simplest case, a civilization only needs to build and launch one successful probe).
In a way, that was an encouraging mistake to make. The default assumption of growing resources can be very damaging to a civilization, particularly one that is already exploiting the entire planet. But resource-bound civilizations can expand to the limit of their feasible transportation technology—-after all, ours did—- and although so far we have done so in an unsustainable way, that needs not be the case, neither for an Earth-wide civilization nor for one colonizing the galaxy.
Empirical evidence suggests that we have grown not only in an unsustainable way, but also in an “unintelligent” way - frittering away lots of energy by pitting regions and countries against each other. As long as national and parochial sentiments cap our collective intelligence, we have no chance on earth or the entire universe to survive, leave apart expanding our influence outside.
Mr. Rinesi,
You make an interesting point about the possibility that the resources available to a civilization will often expand as a civilization expands. This seems very much possible on both terrestrial and extraterrestrial scales. Jacob and I did not explicitly consider this possibility in our paper and we thank you for raising this point.
However, the existence of this point does not eliminate the possibility that resource/sustainability issues can explain the Fermi Paradox: it remains possible that sustainability/resource constraints prevent civilizations from expanding rapidly enough on galactic scales, even given the expanded resources that may come from civilization expansion. If anything, your point might make the Sustainability Solution less likely to explain the FP.
IEET Blog