The Great Colonization Debate
Introduction
Moderator: Several of the pieces assert that humans have a moral duty to preserve ourselves and thus, if colonization is the only way to do this, then it’s morally justified. Others reject any such duty, even implying that we might instead have a duty to allow our own extinction. So is there a moral duty to preserve humanity?
Gonzalo Munevar: There is a biological reason why the survival of the species would be a basic value in the systems of morality of all intelligent beings: All successful organisms have a drive to help the preservation of their genes in generations to come. Thus, many mothers, and fathers also, from many species risk their lives to save their offspring, and sometimes other young members of their group. Their motivation may be love, but that motivation is underpinned by this drive. This same mechanism would likely produce a very strong moral intuition in intelligent species.
Keith Abney: Gonzalo is right, but it’s not just a question of biology. I use my extinction principle to argue that all morally responsible beings have an absolute duty to preserve the existence of beings capable of absolute duties. This echoes Brian’s “moral-centrism” argument, and means that, as long as humanity is the only species clearly capable of moral responsibility, we have an absolute duty to preserve humanity. If we discovered (or created) other beings capable of moral responsibility, then the duty is to keep at least some such beings alive – though not necessarily the humans! This complicates the kind of “existential risk” we so often talk about when it comes to defending colonization: does it apply only to humans? For now, yes; but that could change.
Kelly Smith: I would never have predicted that Hobbes would play much of a role in this debate, but he comes up in two of the papers in this collection. He argues pretty persuasively that survival is the primary right of all beings, not so much because all other duties depend on existence (though that seems true as well) but because it’s not practical to institute a system which requires beings to give up all their interests – nobody (human, animal or alien) would go along with such a system willingly.
Alan Johnson: I agree that humans (like every species) have a right to preserve themselves. I am just not convinced that it is a duty.
Adam Potthast: Yes, it would be helpful to distinguish between a right to preserve humanity and a duty to preserve humanity. One could certainly have a right to life, but no duty to live, as in the case of assisted suicide. However, I’m not sure humanity has a right to preserve itself.
John Traphagan: This kind of moral stuff is really just anthropocentrism in fancy dress, and a particular form of Abrahamic thinking at that. What makes humans so special anyway? Maybe we think intelligence is morally important, but Lori and others have blurred the lines between the intelligence of humans and that of other organisms.
Jim Schwartz: Even if the notion here has historical roots in Abrahamic tradition, we risk the genetic fallacy if we try to use this to, e.g., argue that we are not justified in asserting that human persons are intrinsically valuable (and thus, prima facie, worth preserving). Just because such intuitions aren’t universal isn’t evidence of their mendacity.
Linda Billings: Given that I am not a philosopher by training, my answer to this question is simple: humans have a moral duty to preserve life (human and other), but only on Earth. The argument that we have a moral duty to preserve humankind ad infinitum rests on the assumption that human life is superior to all other forms of life on Earth. This assumption is arguable, at best.
Lori Marino: I do not agree that we have a moral responsibility to only beings who are capable of being “moral”. That is a very specific “social contract” that we already do not abide by, e.g., infants, etc. Using humans as the gold standard is just more of the same anthropocentricism and human exceptionalism that has produced the fraught relationship we currently have with the other animals. So other animals have to “measure up” in order to be considered in this decision? A very real argument can be made that the only species which does not meet a moral standard is our own.
Brian Green: I’d like to ask what’s so wrong with anthropocentrism when it comes to our own survival? Most things in the universe seem to be “centric” in ways that promote themselves, so it seems like that could be a reasonable course of action. That is a purely selfish argument, but if you want to dress it up in ideological terminology, I don’t think it is only Abrahamic. That said, I’m not actually going to stake a claim to protect anthropocentrism, but to protect a moral-centrism, based on this: if we are going to make moral arguments about survival, then those arguments presuppose the existence of humans, since we are the only ones (we know of) having, or capable of having, that moral debate. Any moral conclusion from that debate that says that humans can or should go extinct, undercuts its own argument, by arguing that moral argument and evaluation is of no moral value. Having moral debates presupposes moral creatures capable of having those debates, and if one argues that having such creatures exist is irrelevant, or worse, then one is arguing incoherently.
John Traphagan: I’d like to respond to Brian’s question by noting that human survival does not exist in a vacuum. Humans being “centric” is a large part of the reason that our planet is the mess it has become. What anthropocentrism has brought us is a situation in which we face the possibility of our own extinction as a result of ignoring the damage we have done to other living things on our planet. So what’s wrong with anthropocentrism is that, ironically, it leads in the direction of our own demise rather than our survival.
BrianGreen: John, I agree with you. A “stupid” anthropocentrism of short-term thinking leads to our demise, and we are running that experiment right now. But a more intelligent anthropocentrism, with a longer time horizon, would see that our survival depends on the survival of much more than ourselves. Nevertheless, I do want to reiterate, that while I will play devil’s advocate for anthropocentrism, I am not an anthropocentrist. It’s just that moral arguments require moral arguers, and we are the only ones we know of.
Greg Anderson: Maybe we should replace the word “colonization” with, say, “settlement.” Colonization implies a political structure that may or may not come about and is clearly a loaded word.
Sheri Wells-Jensen: I would nuance that by saying that we have a moral obligation to improve: that is, to colonize yes, but to do it better: to actively unthink systems of oppression that we know exist. To spread ourselves without thought or care would probably result in failure: more planets spiraling toward global warming or space settlements filled with social unrest.
John Traphagan: Greg has a good point here, but “settlement” also is problematic. One has to remember that the people of European descent who moved across the North American continent at the expense of the people who were already there were called settlers. I agree that it is very important to get terminology right. However, we also need to be careful not to neutralize loaded words when they may be appropriate. It is not clear at this point how to best represent the process of sending people to Mars.
Alan Johnson: In an astrobiological context, one might expect there to be extraterrestrial moral agents. If extraterrestrial intelligence exists, especially intelligence capable of technologically advanced civilization, it would seem reasonable that they would have some reasoned approach to analyzing behavior that would equate to a morality. Their moral theories may be quite different from those of humans, but to me it seems likely they would have a morality of some kind. Of course, the Fermi Paradox and Great Silence Keith discusses could indicate that extraterrestrial moral agents either don’t exist or are very rare. But are humans the only source of morality? This is not clear even on Earth. Dale Peterson (2012) argues that chimpanzees, elephants, and many other species inhabit a moral continuum with humans. An entertaining TED talk by Frans de Waal (2011) makes a similar point. Humans articulate ethical theories via language, but the evidence seems to point to the behavior and cognitive basis of morality being more widely distributed than we often suppose. So, even if humans were to go extinct, that wouldn’t necessarily be the end of morality in the universe.
Greg Anderson: I’m not sure morality plays a huge part in colonization. We likely will not colonize space to preserve the species thousands of years hence. That wouldn’t fly politically, and it shouldn’t. If we colonize at all, it will be for other, more proximate, reasons.
Kelly Smith: I see your point Greg, but we have to be careful not dilute the moral question too much with practical concerns. An essential part of what it means to engage in moral debate is to reach for something better, whether it’s practically possible at the moment or not, in hopes that we can create the conditions to make it happen. Progress requires an ideal towards which we strive. It may be that present-day humans wouldn’t agree to settle other worlds in order to preserve non-human life, but that doesn’t mean they shouldn’t.
Lori Marino: This issue has little to do with “moral duties” or “rights” or any such philosophical notions. It has to do with the fact that we are not capable of enacting a successful colonization of another planet. The fact that we have destroyed our home planet is prima facie evidence of this assertion. It is sheer hubris to even consider the question of whether we should “go or not go” as if we are deciding which movie to see this weekend because we really are not in a position to make that choice. Now, we may try to colonize Mars or somewhere else, but we will make the same mistakes we’ve made on this planet. And to the extent that there are any moral duties, they should be to protect other ecosystems from the destructive force of our own species.
Sheri Wells-Jensen: But humans, along with being capable of destruction on a spectacular scale, are also capable of learning, sacrificing and acting wisely especially when our basic needs are met. There is no reason to assume that we would necessarily treat another world in another context the same way we have treated Earth. We are capable of doing better, and if we are intentional about it, we will do better.
Lori Marino: Sheri, I wish you were right but there is every reason to think that we would treat another world exactly the way we’ve treated earth. There is absolutely no evidence to the contrary. The best predictor of future behavior is past behavior. I don’t think this has anything to do with intentionality. We could argue that our species intentionally wants to make life better on this planet (I mean, who could argue that being intentional about having a sustainable earth is anything less than the most important goal.) And yet, we are failing to do that. It is just not in our psychological toolkit.
Carl Devito: The human race seems to have a sense that there are two biospheres on Earth. The human sphere, and the non-human sphere consisting of all non-human life. We seem to think that the non-human sphere exists only for our exploitation. John and Lori seem to be saying that this is a false dichotomy. We are part of the single biosphere that exists on Earth and forgetting that is the source of many of the ecological problems we now face. I think this is a very important point because we are so accustomed to thinking of ourselves as apart, above, and independent of all other Earth life that we automatically fall into that mind-set and carrying that attitude with us as we explore and colonize will only result in the same problems we created here.
Gonzalo Munevar: Some philosophers wonder how we can have duties towards future generations, since it seems doubtful to them that people who have not been born have rights. If these philosophers were correct, however, it would not be murder to program a bomb in the newborn room of a hospital to go off in six months. So we do have a duty to people not yet born. Reasoning analogously, albeit on a much larger scale, we have a duty to prevent the extinction of our species through cosmic catastrophes. That is, to prevent the horrible deaths of billions of other human beings, even if they are not to be born until millions of years from now.
Jim Schwartz: We can also have duties to future generations which do not depend on identifying particular harms. For instance, it has recently been argued that wrongful exploitation can occur without causing anyone to be harmed, and even when the exploited parties benefit. A doctor who severely overcharges for live-saving surgery wrongfully exploits her patients, even though they are better off as a result of the exploitative transaction. So we could try to found obligations to future generations on an obligation not to exploit future generations. This would be more relevant to the issue of what future generations are owed (and thus to what we owe space settlers), which is not the same as whether we ought to continue to bring future generations into existence. So, we may have to talk about something like the interests of the humanity in toto, and that continued existence is in the interest of humanity.
Michael Oman-Reagan: If we accept the idea that we have a duty to protect future generations of humanity, I would like to ask what this “humanity” is? How many generations past or future do we need to go before our ancestors or our descendants are no longer something we would call “human”? If this duty doesn’t apply to other life because of some perceived difference, then how different would our own ancestors and descendants need to be before it no longer applies to them? I hope we can consider the specific history of how and why we have constructed human exceptionalism and then think beyond that naturalized speciesism. Distant generations of our descendants would likely be unrecognizable to us as “human.” If they deserve our moral consideration now, surely all the billions of lifeforms we share the Earth with here and now also deserve at least that much from us.
Kelly Smith: Well, the traditional response that many of us want to defend is that beings capable of moral thinking are thereby morally special. If humans evolve into another form, they would still deserve the highest moral considerability as long as they retain this ability. Similarly, if we discover (or create) other organisms (terrestrial or alien) with this ability, then we would be morally compelled to include them in the club. It’s precisely this kind of reasoning we use to explain why mistreatment of indigenous peoples was so wrong: Native Americans were different from European colonists, but not in any way that should matter morally. So, the degree to which preservation of humanity is a duty may depend in part on the extent to which humanity is the source of morality (strong sense) or at least a rare embodiment of moral capacity (weak sense).
John Traphagan: I don’t see rights as inherent, but as cultural, so I find this entire line of reasoning problematic. That said, if a species so thoroughly upsets the ecological balance that it risks not only its own existence, but the existence of other species, can it lose this right? Also, I’m not at all sure that humans really believe that survival is the primary right of all beings, because we clearly do not respect that right in any species other than our own. For example, we do everything we can to fight against viral and bacterial infections and kill invasive species that might damage our crops, even if the only damage to humanity is that we lose profits (we can grow other crops). Humanity itself seems to function more like an infection to the Earth than anything else, so I would ask at what point is our “right” to survive outweighed by the rights of all of the other species on Earth to survive?
Moderator: Let’s pursue that. Is any duty we might have to preserve morally capable beings (and by extension, humans) contingent on their good behavior?
Lori Marino: It’s deeply perverse to say humanity must be saved by destroying other ecosystems because it’s humanity’s fault we are in this situation in the first place. If we were holding a job interview for potential colonizers, we have to admit that humans are terrible prospects for the job, in the same way a child abuser is not the ideal choice for a babysitter. What objective person would hire humanity to colonize a virgin planet, given its abysmal past performance in caring for the Earth’s ecosystem (overpopulation, climate change, mass extinctions)? What’s more, the “we have learned our lesson” myth is just that – show me the evidence for this!
Greg Anderson: First, what constitutes “good” behavior is not obvious; it varies with philosophy, circumstance, goal, etc. Second, we should be careful about judging a civilization far ahead of us technologically and scientifically, and hopefully ethically as well. I doubt the people who make these decisions will bear much resemblance to child abusers – or to me.
Keith Abney: This seems to be a justice argument, one effectively invoking the death penalty and collective guilt: we have been bad enough as a species that we collectively deserve to die. But like many collective guilt arguments, it seems unjust to many of the individuals involved. Even if you think that Scott Pruitt has done horrible things, it doesn’t follow that all other humans (like, say, Lori Marino!) deserve to be punished. In particular, it demands an accounting of our obligations to future generations – do they all deserve punishment? Should we ascribe the sins of the parents to their children? Is it wrong for them ever to have been born? At what point can we say, not merely of any individual human, but of collective future humanity, that it is better never to have existed? This also demands an accounting of the morality of the passive/active distinction: is it equally right (or wrong) to allow humanity to cease to exist, as to cause it to no longer exist? We presumably don’t think it would be ok for someone to cause the extinction of humanity, so why should we think allowing human extinction would be morally good?
Lori Marino: This is not about punishing our species for not being good citizens on the Earth. It is about the plain and simple fact that we are just not up to the task of moving to another planet and living there successfully.
Michael Oman-Reagan: I agree with Lori here. The very practices humanity would need in order to survive in space colonies or on another planet like Mars are those we fail to engage in here and now on Earth. In space we must treat our environment as the most precious thing we have, habitability must be a priority, not profit. Cultural difference and other forms of diversity are our best survival toolkit, one we have developed as a species over millions of years of evolution and thousands of years of history. In order to survive, humans living in space will need to recognize and protect everyone’s right to housing, healthcare, education, food, water, and safety if the species is to survive. But today on Earth we see massive environmental destruction, mass extinction, profit chosen over habitability, refusal to embrace diversity and difference, and the greatest refugee crisis since the second World War. We are not protecting our environment, or each other, in the ways that we must. We may be on the verge of having the technological infrastructure to move into space, but we do not yet have the cultural, social, and moral infrastructure.
Jim Schwartz: But can’t we agree that past behavior doesn’t matter as much as future behavior?
Keith Abney: Yes - isn’t the collective behavior of humanity getting better on exactly the issues of concern? After all, the environmental movement didn’t exist 300 years ago. Moral improvement, though slow and prone to hiccups, does appear to exist. But Jim, Lori, and Adam bring up important issues; from a virtue ethics perspective: if preserving humanity makes us into worse people, with a vicious character, then it’s not worth it. In that way a virtue ethics approach differs from a deontological approach that claims we have an absolute duty to preserve beings capable of morality, regardless of the consequences.
Sheri Wells-Jensen: We are getting better because we choose to make it better and to fight the cultural inertia that pulls us back. If we don't change, we fail on Earth and our attempts at colonization will also eventually fail. Success at colonization necessitates acting wisely. We go into space consciously and create structures that will guide the colony toward best practices ecologically and culturally… or we won't survive. And we can do this because we will be starting in a context where everyone's basic needs can be met.
Linda Billings: There’s also the argument that all life on Earth evolved to live in Earth conditions and thus should stay put. Planet-colonizing advocates claim we need to move on because Earth might not be able to sustain human life for long. If humans can’t figure out how to adapt to, or arrest, changing conditions on Earth – then I can’t see how humans could figure out how to adapt to a totally alien environment.
Keith Abney: Lori and Linda seem to assert an important practical test: if we cannot successfully create an off-world colony, it makes no sense to say we ought to do so. After all, “ought implies can.” And of course, humanity’s first attempts at colonization of the Moon or Mars are hardly guaranteed to succeed; so, what are the minimum odds of success that would make the attempt morally legitimate? If existential risk is a primary driver of the moral argument, the Extinction Principle would indicate almost any odds above zero make the attempt worthwhile. But Lori and Linda may also have an additional test in mind: humanity has to become more ecologically conscientious and more capable of being good stewards to justify spreading its impact elsewhere. If so, how much better do we have to be to justify the attempt?
Lori Marino: Keith, the answer is simply “a whole lot better than we are.” The bar should be set pretty high and right now we are nowhere near the point where we should be considered an ecologically responsible species. We are nowhere near even a low bar. And it is doubtful we will ever be.
Sheri Wells-Jensen: I can agree with Lori right up to that last sentence. Doubt is not more logical than hope. Yes, there is considerable inertia pushing humanity along in destructive directions. But, we can (and I believe will-because-we-must) respond to new situations in new and better ways.
Michael Oman-Reagan: And beyond whether initial efforts at settlements in space would be successful, we need to think about what kind of structural foundation we would be building for humanity in space if we exported the systems we use now on Earth into space. There is no reason to believe that systems like capitalism, structures like the nation state, and institutions like militaries will magically work in space, when on Earth they continue to produce massive inequality, famine, war, and ecological destruction.
Adam Potthast: I think we have to be careful saying we should solve our problems here before taking them to a separate planet. Humanity would still have a darn good story if it took us a couple of planets to get the whole being-good-to-each-other-and-our environment thing right. I don’t see a stronger ethical argument for only giving a species one planetary chance to get it right anymore than we have a duty to solve the problems of our own country before giving aid to others (or getting your first house perfectly remodeled before buying a different one that you like more). It’s possible another world would provide better conditions for humanity to flourish than this one.
Adam Potthast: If our only option is to trample on individual human rights in order to preserve the species (forced pregnancy and forced birth, for instance, as happens in the reboot of Battlestar Galactica), then I can’t see the “right” of self-preservation being legitimate. Say the Earth will encounter an existential crisis in 100 years and the only option for humanity’s survival is to use all of the remaining resources on Earth to launch a ship that will carry 100 people (while millions die from lack of resources on Earth). Would this “right” imply that we can deplete our resources to launch the ship?
Brian Green: That is an interesting question, Adam. But like the case you discuss in your piece where we have to decide whether to send a ship of “bad people” if its chances of success are much higher than one with “good people,” it’s an extremely artificial thought experiment. Why must we have a ship with just bad folks? It makes no sense. However, since that is the scenario and it does highlight an interesting point about the moral value of even morally bad humans, I will argue in favor of the bad ship folks. Why? Because all of our ancestors, if you go back far enough, were from the bad ship. One need not be a fan of Douglas Adams’s Hitchhikers Guide to the Galaxy (where humans are descended from the cast-offs of a previous alien race) to acknowledge that many of our ancestors were actually extremely brutal people. Colonizers and slave-owners. Thieves of other’s land. Child-abusers, rapists, and murderers. One need not be American to recognize some of these historical truths – there are no utopias on Earth. Think to yourself how far you have to go into your own ancestry before these pathological individuals appear. For some of us it might be far… but for others not far at all. And yet here we are, reading this, and we are hopefully not all that bad. The surest way to never improve is to not exist. Existence is the precondition for moral improvement. Therefore, if morality has any value at all, humans must exist, even if they are very bad humans. A bad start is better than no start
Sherri Wells-Jensen: We can certainly all agree that, if we colonize, we will have to do better, or the colony won’t survive. The best chances for a colony’s survival are wrapped up in ethical behavior: by including everyone in rethinking social and economic systems and in acting justly. This is not easy, certainly, but there seems no a priori reason to believe it’s impossible. Yes, we have been the destroyers of many beautiful and essential things… and we have also been working hard in places to be kind and to undo damage that we have done. The last word has not been said over us yet: hope that we will improve is as logical as despair that we will get worse. The worst of what we are is pretty bad… the best of what we are is incredible. The jury is still out. The fact that we recognize our own failings is a hopeful sign.
Gonzalo Munevar: Sheri, your remarks in this regard, as well as Jim’s and Brian’s, are well taken. I would like to add that those humans who undertake colonization will (eventually) insist on paying attention to environmental concerns, for otherwise their colony will not survive. Most humans would not be good at it, but they will try. Most humans are not good enough to play classical music well (I am awful), but a few are. We will send the committed and the capable who volunteer.
Kelly Smith: It seems like, in many ways, this comes down to whether we are optimistic or pessimistic about humanity’s future. If immorality is not heritable (and it’s not), then I would argue it’s immoral to condemn future generations for our sins. I choose to adopt (guarded) optimism myself.
Adam Potthast: Ok, maybe immorality is not heritable, but it’s interesting to examine why it’s not and how future generations improve. I would argue it’s all about the mix that children of bad people find themselves in. If the pool of people gets increasingly bad, we should expect immorality to become the status quo for future generations. (Christians can invoke the notion of grace, but more secular defenses of optimism would require belief in goodness being more powerful or random chance pushing people to better behavior).
Kelly Smith: But you are still talking about the heritability of immorality, Adam – you just point out this can be achieved by cultural as well as biological means. This is true, of course, but I don’t see the argument for cultural inheritance as being any more supported (in the long term) than a purely biological one.
Brian Green: There have been some apparent cases of hereditary criminality (see Brunner et al., 1993). But even if immorality is heritable, it still is morally wrong to condemn future generations for things they have not yet done and may never do. If we allow the denial of the value of the lives of criminals then we are implicitly saying that, morally, “it is better to be dead than bad,” which not only forces an impossible standard of perfection upon humanity, but also somehow assumes that we critics meet that perfect moral status (which I seriously doubt!). All humans are both good and bad, as Aleksandr Solzhenitsyn (1974, p 168) noted: “If only it were all so simple! If only there were evil people somewhere insidiously committing evil deeds, and it were necessary only to separate them from the rest of us and destroy them. But the line dividing good and evil cuts through the heart of every human being.”
Adam Potthast: That morality could be culturally heritable is a good way of stating the point I was trying to make, Kelly. Usually, on Earth, the diversity of cultures, families, and social connections gives us some insurance against bad conditions in the past creating bad conditions in the future. There is much more of a risk of the future morally resembling the past if one launches a monoculture to colonize another planet. If morality isn’t heritable, each generation has just as much of a chance to fall into immoral ways as moral ones (unless there is such a thing as grace).
Koji Tachibana: Actually, we have good reason to suppose, based on past studies of humans in isolation and confinement, that colonists would be become less moral in the stressful environment of a new colony.
Moderator: Let’s change gears a bit and talk about the other inhabitants of Earth. Several contributors argued that, in the long run, moving pollution and resource exploitation off Earth may actually lessen the pressure on living things here, perhaps staving off an “end times” scenario. But other contributors worry that bad environmental ideologies (e.g., disposable Earth) may either come back to Earth from colonies or be reinforced here through colonization ideology. So, is colonization, in the long run, a good or a bad thing for all of Earth’s inhabitants?
Alan Johnson: Threats to Earth are also threats to Earth’s non-human inhabitants. Any colony that is self-sustaining will have to include a diverse terrestrial ecosystem, not just humans, so we would not be alone in the lifeboat. The idea of bringing a substantial amount of Earth’s biodiversity along to create a self-sufficient life-support system raises an interesting prospect for endangered species preservation. For instance, I can imagine that an animal like the pika, a small mammal that is adapted to cold, high-altitude habitats on Earth, might do well in a terraformed Martian environment. That said, I am extremely ambivalent about the prospect of preserving species by introducing them to other worlds while they go extinct on Earth. I would much rather see emphasis placed on protecting Earth and its wild species, reducing the impacts of anthropogenic climate change (a major threat factor for the pika), and so on. Also, a pika on Mars will be an introduced (invasive?) species in an engineered environment, and in that sense a human artifact not really equivalent to its wild counterpart. Still, in some hypothetical future, if it came down to either preserving pikas on Mars or having no pikas at all, I’d be tempted to assist the critters in colonizing a new planet (They are awfully cute, after all).
Greg Anderson: With any luck, the vast majority of humanity will live on Earth indefinitely; colonization will expand our technology and our perspective.
Gonzalo Munevar: In the shorter term, a strong human presence throughout the solar system will be able to prevent catastrophes on Earth by, for example, deflecting asteroids on a collision course with us. This would also help preserve the rest of terrestrial life -- presumably something the critics would approve of. But eventually, we should be able to construct space colonies at la O’Neill, which could house millions. These colonies would be positioned to construct massive solar power satellites to provide clean power to the Earth, as well as set up industries that on Earth create much environmental damage. Far from messing up environments that exist now, we would be creating them, with extraordinary attention to environmental sustainability.
Jim Schwartz: I don’t think that space settlement will affect Earth all that much. There is a lot of research coming out suggesting that easily accessible space resources are very scarce and will only arrive in small quantities over long periods of time (Elvis 2014, Crawford 2015). So, I don’t think that we’ll ever see much space manufacturing for terrestrial consumption - best to leave space resources to space dwellers. Frankly, I don’t want to live in the world where it’s cheaper for me to buy nickel from space. Things have got to get really bad down here for that to happen. That being said, since few humans would migrate any time soon, we still have powerful incentives to preserve the Earth even if we pursue colonies in space. Those who do migrate will have to live in a very harsh world, dependent on their ecosystem, so there is good reason to think this might breed the “super-environmental ethic” critics say they want.
Brian Green: Jim’s point about a harsh extraterrestrial environment fostering respect for nature is worth further exploration. Those who will live in extreme space environments will not only pioneer technologies for sustainability, but ones for restoration and creation (on our heavily damaged planet, sustainability is not good enough, we need environmental restoration). This “super-environmental ethic” will grow and hopefully contribute towards the amelioration of our bad practices here on Earth. Furthermore, we have to realize that solving Earth’s environmental problems is extremely difficult and so will take a very long time. And we can do this while also pursuing colonization, so we shouldn’t get caught in the tow of a false dichotomy.
Lori Marino: It isn’t a false dichotomy. We cannot do both at the same time because we cannot even do one! What’s more, if humans do go they should not bring other animals with them because the other species did not sign up for this!
Kelly Smith: But don’t we normally consider it justified to make decisions on behalf of those who can’t express their wishes (e.g., infants, pets, etc.), at least if we have good reason to think this is actually in their interests? If we must use other organisms to make a sustainable settlement, and we insist that we can never do this without their expressed consent, then we can never colonize. So, shouldn’t the question really be whether taking other inhabitants of Earth with us is actually in their long-term interests?
Michael Oman-Reagan: I hope we never meet an extraterrestrial intelligence that thinks about us that way, while at the same time being entirely unable to communicate with us to even ask us what we think is in our long-term interests.
Keith Abney: If we have a major extinction event on Earth (e.g. large comet/ asteroid impact, full-scale nuclear war, etc.), the only hope for most or all of the rest of Earth’s biota is if we have successfully and sustainably colonized another planet, enabling other life to exist elsewhere. If one thinks avoiding the extinction of current species is a moral priority, having a backup planet for ecosystems seems terribly important.
Lori Marino: We are already going through a major extinction event and we are doing nothing to mitigate the effects on other species. If we add a sudden catastrophe like an asteroid impact is it realistic to think that we are going to be worried about the survival of other species? The only species we are going to care about are those we eat and use for our own purposes. Let’s get real!
Keith Abney: Of course, Lori is correct that, in geological terms, we have an ongoing extinction event caused by humans, and she’s likely also right that humanity would act even more selfishly if we wait until a catastrophe is imminent. To my mind, that’s all the more reason to get started sooner, when those concerned with preserving healthy, sustainable ecosystems could make a difference in the conversation about how colonization proceeds.
Sheri Wells-Jensen: We know we behave badly when surprised or threatened, so I agree with Keith: begin now so that the beginning can be a careful one.
Moderator: Ok, so what are your thoughts as to what we should be focusing on now?
Gonzalo Munevar: Whether Mars has extant life or fossils, the scientific treasure it offers is not only tantalizing but of truly extraordinary importance. This means that we should not transform Mars in any significant way until we are able to do a proper scientific exploration of it. Such exploration will extend to the history of the geology, atmosphere and climate of Mars. Our sister planet has much to teach us. At any rate, in the next several decades, we are unlikely to have much more on Mars than small outposts that will devote themselves to scientific exploration and will grow much of their food in greenhouses. Anything that could really be called “colonization” would probably have to wait a century, and even then would be quite small. Truly big domed or underground cities, let alone terraforming, must wait a long time. Devito is right.
Carl Devito: Mars, at its closest is about 45,000,000 miles away. It has a very thin atmosphere of little use in blocking dangerous radiation from the sun. A colony there would need constant supply missions from Earth. In a dangerous situation, should one arise, the colonists can expect little help from home-- 45,000,000 miles is a long trip. We have an international space station and have learned much about setting up man-made habitats in space. We can put such a habitat further out in space with much less effort than a settlement on Mars. The Moon is where we should start by putting a radio observatory on the dark side. Many of the instruments there can be automated and used by people in a safe habitat. Such a habitat can easily be re-supplied since the Moon is only 250,000 miles away.
Greg Anderson: I agree with Carl. Settling the moon should be our next step.
John Traphagan: We should focus on science for now. In part I think this is appropriate because it allows us to focus on the problems we face on Earth, rather than simply bringing those same problems to other places like Mars. Let’s explore space as a way of learning that will help us address the problems we’ve created here; in other words, let’s engage in applied research that is aimed at helping us correct the tremendous mistakes we have made on Earth. Through that, we may be able to learn how to build sustainable societies, rather than societies based on consumption, and at that point in time it would make sense for humans in larger numbers to begin to “colonize” other planets such as Mars. We should not be engaged in expansion if it simply means recreating the mess we’ve made here on other planets. Colonization has the odor of running away from the problems we’ve created here; if we do that, we will simply bring those problems with us. We need a major change in how we think about what it means to be human—we need to stop seeing our species as special and start seeing it as part of a collection of species. In my view, as long as we bring the Abrahamic tradition (and other traditions) of human exceptionalism with us to other worlds, we are doomed to repeat the same mistakes we have made here.
Michael Oman-Reagan: Space scientists often talk about analogues – environments and places on Earth that stand in for places on other worlds, like Mars. I think that if someone wants to figure out how to build a successful space settlement one day, the best place to start is to see if they can use Earth as an analogue. Transform human civilization into a globally sustainable and just community, devoted to the protection of our planet, its habitability, the species we share it with, and one another’s freedom and well-being. If you can do that, you can build long-term settlements elsewhere. Though whether you should is a different matter.
Carl Devito: I see science as basically a learning activity. The main reason for space exploration, in my view, is to learn. Mars presents us with a unique opportunity. It is hostile enough, and far enough away, to preclude large scale human migration. So colonization, if it occurs, will take place in the far future. We will not rush there and simply run from the mess we have made here only to make it again on another planet. Since we have international cooperation in space, at the space station, for example, we can use the expertise acquired there to put a habitat around Mars for the purpose of learning; learning about an alien weather system, and alien geology (marsology?), and an alien ecosystem (if there is one), with minimal disruption of those systems. We may learn enough to prevent future colonists (should there be any) from making the same environmental mistakes we have made here.
Alan Johnson: First, I agree that we should put the emphasis on exploration and learning about the other places in our solar system. Much of this exploration can probably be done most efficiently by robots, but human missions probably will (and should) play a role. As we learn more about the places we might eventually colonize, we will be in a better place to make decisions about whether and how to colonize. I especially think we should make a more thorough effort to determine whether or not (microbial) life is present in places like Mars or Enceladus, because I think that the presence of even microbial life should place ethical constraints on colonization, although it would not necessarily preclude colonization. However, even on lifeless worlds, I would argue that there may be values (aesthetic, recreational, spiritual, etc.) associated with extraterrestrial environments analogous to the values we associate with wilderness on Earth. We need to weigh carefully what is lost and what is gained in the choice to colonize. Second, I think much more needs to be worked out in terms of space policy and governance of space colonies. As Greg points out, the politics of space settlements are likely to be complex. What will the attitudes of Mars colonists versus Earth-dwellers be regarding proposals to exploit Martian resources or terraform the planet? I can imagine a situation like that which has existed for decades regarding oil drilling in the Arctic National Wildlife Refuge in Alaska. Multiple attempts have been made to introduce legislation in Congress to allow oil development. Members of Congress from Alaska have generally voted in favor of these efforts (reflecting the majority opinion of Alaska’s citizenry), but, until recently they were thwarted by environmental concern most prominently expressed by non-Alaskans. How should planetary management disputes between Mars colonists and Earth-dwellers be resolved? Right now, we don’t have a clue.
Sheri Wells-Jensen: And we need to put some serious energy into thinking about how we will deal with the social constructs necessary to set up a coherent human group far from earth: who gets to go? Who has to go? What kind of judicial/command structure is necessary? What disqualifies a person from going? If we are not careful, those choices will be made without examining underlying assumptions. Well intentioned people make mistakes because they don't consider all the options. We don't want to thoughtlessly map a military or capitalist or any other kind of -ist structure onto this group.
Linda Billings: Rather than pursuing conquest, colonization, and exploitation in space in the tradition of the European explorers of the Renaissance, we should be focusing on space exploration in the tradition of Alexander von Humboldt – for the sake of discovery, learning, knowledge, understanding.
Lori Marino: I agree with Linda. And I’ll say it again. It is preposterous to even consider colonizing Mars, the moon, or anywhere else in space when we have a planetary crisis going on right here on earth. What should we be focusing on now? How about restitution, reconciliation, and compensation to the other species we share the planet with in the full knowledge that we are the cause of the crisis. Our species has only one choice and it isn’t to colonize Mars or not. It is to decide whether, in the final analysis, we want to be able to look at ourselves in the mirror or not.
Greg Anderson: But what if dealing with the problems of Earth requires, among other things, expanding into space?
Jim Schwartz: We have a principled and long-term duty to colonize, but exploration is a much stronger duty over the short run. There are ways in which science and settlement can work together, but there is no guarantee that settlers would have the spare time, expertise, and resources needed to scientifically investigate their surroundings. They may be too preoccupied with mere survival. You can always colonize after scientists have had their chance to look at the pristine environment. But you can’t always conduct effective science after settlers have mucked up the place. And, as scientific exploration will always be less risky and less expensive than human settlement, it isn’t that unrealistic that we get what we can from the former before attempting the latter.
Lori Marino: Why do we have a principled and moral duty to colonize? I question that very premise. And if you ask native peoples in North America how that kind of thinking on the part of Europeans worked for them you would get a very different answer.
Kelly Smith: Alan is certainly right that the ethical issues involved in a colony on an inhabited planet are very different from those on a lifeless world. He’s also right that this does not necessarily mean we should be free to do whatever we wish even if we are not harming other living beings. But these are very different issues and we should be extremely careful with our analogies. For example, making comparisons between extraterrestrial colonies and the historical evils associated with colonialism on Earth does more to obscure than to enlighten. Colonialism was horrible, but it’s hardly an appropriate analogy for a lifeless world, or even one inhabited only by microbes.
Greg Anderson: Exploration to expand our science and technology is important, but settling space must also have an economic driver. A larger economy is clearly needed to meet the challenges immediately ahead and moving into space for profit should be one component of an overall strategy.
Sheri Wells-Jensen: I find it hard to get exercised about damage we might do to rocks. Yes, we should do all the science we can first, organizing the colonies or outposts or mission hubs (whatever would be a good word) around science, but if I have the choice between uglifying the moon and having my grandkids sicken for lack of some lunar resource,… then the moon is going to get ugly.
Michael Oman-Reagan: If we have a duty to our descendants here on Earth, don’t we have a duty to future possible life that could evolve on other worlds from microbial life? If there are microbes on Mars, I think Mars belong to them. If there is water on Mars, that water belongs to them.
Alan Johnson: Michael, I’m surprised to hear you taking this position, given what I interpreted as your endorsement of Lynn Margulis’ idea of colonization as Gaian reproduction. She envisions a process of ecopoesis, seeding Mars with microbes from Earth to foster the development of a planetary biosphere or new Gaia (Margulis & West 1993). Surely this would wreak havoc with indigenous Martian microbes, although, to be fair, Lynn Margulis was pretty confident that Mars is, in fact, lifeless. Still, I think she would see the establishment of a planetary biosphere as a good thing, and whether the microbes originated from Earth or Mars, or some mix of both, as being of lesser importance.
Keith Abney: As Kelly says, until we discover alien persons, colonizing other lifeless or microbial-inhabited worlds seems to raise very different moral issues from those raised from Europeans taking over the lands of indigenous peoples and exploiting them. For the foreseeable future, though, if the primary goal is exploration and research, there will be little reason to ever send humans; robots can do it better, faster, and cheaper. And even careful astronauts will inevitably interfere with whatever natural systems are in place. So, I don’t see any real legitimate purpose for human spaceflight other than settlement.
Kelly Smith: I also think we need to explicitly distinguish between short term and longer term time frames in our discussions, since they generate different kinds of ethical questions. Thinking short term is easier for scientists and engineers because it is firmly rooted in what we can do right now. And in the short term, it’s easy to say we should focus on science – too easy, in fact. There is little debate about this, in large part because we are just not capable at the moment of doing much more. Given that, the fact that we are here arguing about colonization demonstrates that we are very interested in the bigger questions that come up when you expand the time frame. We have to think ahead to when colonization is actually possible. But there is a real danger in that, the further we get from what is practical now, the easier it is to employ vague and impractical ideals. Thus, the perfect becomes the enemy of the good, as vague and perhaps unattainable standards are put forward as preconditions for colonization. Would it be best if we created a perfectly sustainable, environmentally responsible system on Earth before launching colonies in space? Absolutely! But we must go on to ask: 1) What exactly does “perfectly sustainable and environmentally responsible” mean and 2) How will we know when we have gone far enough in this direction, since there will always be those arguing we have not yet done enough?
Keith Abney: We should also be careful assuming that we have plenty of time to set up sustainable human colonies. Given that robots will work better in space, we can expect their utilization to continue and to spread through space, but that has unwelcome implications. If you buy my interstellar doomsday argument, then we should assume that humanity probably has very little time, possibly only a few decades and almost certainly less than 250 years, to get humans off Earth. If we all agree that colonization is very hard and will take a long time to perfect, isn’t that an argument for starting now?
Brian Green: The bottom line is that we can’t do “Science-First!” if humanity does not exist. Science-First! relies on the assumption that humans exist – therefore if we want to put science first we actually need to put science second and put humanity’s survival first.
Moderator: Perhaps we can have our cake and eat it too by pursuing alternate, non-violent, means of human expansion? Several of you have hinted in your papers that there may be such approaches, perhaps based on a recognition of our fundamental nature as holobionts (communal organisms). Is there an alternative and, if so, what might it look like?
Alan Johnson: Humans have quite a legacy of creating ecological upheaval when they colonize new territory. The “Pleistocene overkill” hypothesis, although not universally accepted, does make a strong case in my opinion that the expansion of Clovis culture played a role in the extinction of mammoths and other megafauna in North America. It also seems that the expansion of Polynesian culture to various Pacific islands precipitated extinctions, such as the loss of moas (large flightless birds) on New Zealand. Alfred Crosby’s book Ecological Imperialism (2004) documents the biological consequences of European expansion into the New World. Some of the consequences of our colonization are intentional, but many are unintended. I don’t know if there is a way that we can colonize other planets without the violence that has been typical of the past, but I sure hope so. My only suggestion is to go slow and start with steps that are least likely to have serious or irreversible consequences. Thus, my preference for robotic and limited short-term human exploration before any attempt at permanent colonization.
Greg Anderson: But let’s remember that the people who make the decisions about other worlds won’t be Clovis hunters or nineteenth century imperialists. The question is not about Clovis, it’s about us, about human nature. Can we learn? Can we act according to our better angels? If we cannot – forever, under any circumstances, period – then this project, and much else, is a waste.
Michael Oman-Reagan: I wonder how it might change our perspective if, following Lynn Margulis, we think of colonization as a form of reproduction. This focuses attention on the question of what exactly is being reproduced when we talk about settlements on other worlds. Whose lives, cultures, values, and practices are we reproducing? At the moment, space settlement plans reproduce heterosexual, white, male, Euro-American ideologies in space. That isn’t actually reproducing “humanity,” let alone Earth, but just one small privileged faction of our species, along with their propensity to oppress anything they encounter that is unlike them.
Brian Green: This is a great question Michael, but I think we need to take a step back and recognize that reproduction presupposes existence. We can’t reproduce, much less reproduce particular aspects about ourselves that some of us like, if we do not exist. Therefore, the first necessity is to safeguard our own existence by reproducing any human civilization at all, off of Earth.
Alan Johnson: The process of Gaian reproduction, as described by Lynn Margulis (1993), is not so anthropocentric. She sees artificial biospheres created by human colonists as “an expansion and metamorphosis of Earth’s original biosphere by members of all of the five kingdoms of life” (emphasis added). Throwing traditional concerns of planetary protection aside, she envisions the intentional microbial contamination of the Martian environment, resulting in a “cesspool” that would be quite inhospitable to humans for many centuries (Margulis & West 1993, 279). So, as Michael asks, what exactly do we wish to reproduce? Life? Then, microbes play the pivotal roles and humans are instrumentally valuable as vectors to transport microbes to new environments. Or is reproducing civilization the primary goal, as Brian emphasizes? These goals may be compatible in the long-term, but which we choose to emphasize could influence the approach we take to colonization.
Sherri Wells-Jensen: Well, if we don’t do it better: if we send the same ol’ nonsense out that we have here… we’ll get the same ol’ nonsense back and the colonies will poop out. We have an ethical duty to sabotage the elitist notion of colonization: As people thinking about these things, it’s our job to infiltrate, convince, convert and take over. If I’m right, and I bet I am, that colonies have a better chance of surviving long term if disabled folk are in crucial roles aboard the colony vessels, that’s step one toward taking down the patriarchy. And that is our job.
Linda Billings: I must note though that there is little cause for optimism here, since colonization is a project driven by elites and thus will benefit only elites. Colonization is an ideology-driven exercise that, at the very least, has not received sufficient critical scrutiny. As John and Michael note, the discourse on space exploration and exploitation is dominated by fundamentally religious belief systems like manifest destiny, exceptionalism, and Russian cosmism, which see everything on Earth, and beyond, as mere resources to be exploited for human ends. As long as this is the case, we should expect other worlds to be treated very badly indeed.
Lori Marino: I agree. Nothing will be done to ensure representation because nothing is ever done. Representation is in the hands of the powerful.
Sheri Wells-Jensen: Representation is in the hands of the powerful only until we insist otherwise.
John Traphagan: And the vast majority of humanity is desperately poor and probably doesn’t care much about such things. Certainly, there are many human populations that either oppose this (e.g., Native Americans) or are indifferent (e.g., Buddhists).
Kelly Smith: Hmmm…well, I see your point John, but it doesn’t seem to be a good idea to allow every group on Earth veto power over colonization as there will always be some group opposed to any action we propose. And some of us are skeptical of the assumption that most people don’t care about colonization. While it is certainly true that most humans would not benefit directly any time soon, it may also be true that most humans: 1) will benefit in the long run (a time frame we are terrible at factoring into our decision making) and 2) would actually support colonization, if asked. Don’t we at least have a duty to conduct more surveys of public attitudes in order to discuss this in a scientifically respectable way? More generally, it’s worth asking if it matters that much, in the very long run, if (as always) those who take these kinds of “opportunities” will almost certainly be either the very rich (true believers) or the very poor (the desperate)?
John Traphagan: I don’t think we need to have veto power, but we do need to have multiple voices involved in all discussions about the ethics and desirability of colonization of space—and those voices need to be given equal weight. The problem now is that the discourse is heavily dominated by Westerners and, thus, by Western-style value systems. The West does not have the right to speak for the entire planet.
Linda Billings: I’d also like to note a Pew Research Center poll (2018) recently asked respondents to rank priorities in space exploration. They ranked studying climate change first and sending people to the Moon and Mars last.
Brian Green: But surely any self-sustaining space settlement, even if very non-diverse, would be preferable to none at all. Moreover, any human settlement, if allowed to grow and flourish, has the potential to become diverse over long periods of time (though admittedly, it would not be the same kind of diversity as we have here on Earth, now). If humans go extinct, there will be no human diversity. That said, diverse settlements are much preferable to non-diverse ones for a wide variety of reasons, not the least of which are practical reasons focused on problem solving, as well as the preservation of a variety of human knowledge and culture (the fruits of thousands of years of human effort and ingenuity).
Michael Oman-Reagan: Can a non-diverse settlement survive? I don’t think it can. Our diversity has been the key to our survival across radically different environments as we moved around the planet. And this practical problem-solving contribution is often written out of history in favor of myths about straight, white, Euro-American men working alone to solve the great problems of the time. It’s important to note that we are a group mostly composed of white men, with few exceptions, discussing the fate the planet and our species. These conversations, even when we think of them as debates, and make efforts to diversify them as the organizers have, are still incredibly insular and dominated by the same voices.
Gonzalo Munevar: I find it ironic that those who are most unsympathetic to the value of saving humanity from extinction also insist that all humans should be consulted on whether to undertake colonization. I would bet that most humans would be aghast at the view that we should do nothing to prevent human extinction.
Adam Potthast: There does seem to be some conceptual baggage being smuggled into the idea that we are doing violence to other worlds, especially if these other worlds don’t contain life. I wonder if the violence is primarily to people’s romanticism about other worlds rather than to the worlds themselves. Surely some of that romanticism could be sacrificed if it meant a dramatic increase in living standards here on Earth? Are there parallels to the purity of the anti-GMO debate here?
Kelly Smith: Well, I think we can all agree that the way the debate has been framed so far is pretty unrepresentative of alternative points of view, which is a large part of the motivation for this collection. Certainly, all aspects of a decision to colonize should be carefully considered by a much more representative group than we have seen so far. But we have to accept the possibility that even a more inclusive decision-making process may ultimately endorse actions many (in particular academic elites like us) will find unpalatable. An expansionist ideology might be an important factor in determining the long-term success of a society. If so, it might be best to colonize despite well-considered objections, lest we recreate the Shakers’ philosophical prohibition on sex, and with similar results.
Moderator: How about the Mars One question: Is it morally ok to send humans into what will initially be a hellish situation, even if they consent?
Jim Schwartz: Good question. What kind of lives will we provide to future settlers and subsequent generations? Forcing people to toil “for the sake of the species” seems exploitative. I’d bet most Institutional Review Boards wouldn’t sign off on a “settlement experiment” involving human subjects.
Koji Tachibana: Certainly, colonization with present technology would be an ethically suspect experiment. Not only would colonists have to endure harsh physical conditions at extreme risk to their lives, but we have good reason to suspect that these conditions would actually degrade their ability to act in ethically appropriate ways.
Greg Anderson: Right. It’s just not OK. We are nowhere near ready to settle Mars – not scientifically, not technologically, not economically, not culturally.
Keith Abney: For sure. Any flight to a place as nearby as Mars will almost certainly be a death sentence in the near term. Such an experiment would never pass muster with an ethics review committee on Earth.
Sheri Wells-Jensen: Ethical? Is adventure ethical? That's what we're talking about here at least from some perspectives. Was it ethical to risk (and lose) lives trying to land on the moon? What about lives lost testing new kinds of airplanes? Cars? Domesticating animals? Heaven save us from a world controlled by the IRB.
Michael Oman-Reagan: And even if we decide it’s morally acceptable to send consenting humans to Mars, what about any children they choose to have? We might be able to keep people alive in space, but the space exploration and settlement community has yet to seriously address the issues of planetary reproduction and interplanetary consent, including inter-generational consent and non-human consent.
Linda Billings: I agree. Having worked with NASA’s space life sciences program for many years, I know a little more than your average person about the effects of living in a space environment. I highly doubt that Mars One recruits are truly fully informed about the risks they would face in getting to and living on Mars.
Kelly Smith: I worry about this as well. It’s certainly not the case that, just because someone says, “Yes” when asked, that this settles the moral question. We need to be careful that colonists fully understand the risks (not an easy task) and are given the opportunity to refuse. Ideally, anyone who goes on a colonization mission should also have other options they find palatable, so they are not acting out of desperation. On the other hand, people regularly consent to important jobs we would all probably refuse (e.g., garbage collection, military service) – in part because they lack the options afforded by the kind of high socio-economic status we all enjoy. It always comes down to a question of alternatives: when experts feel a course of action is ill-advised, should they decide for everyone or should they allow people to make their own (often stupid) decisions? After all, paternalism also has a long and highly suspect history.
Jim Schwartz: I think this question is even more complicated than is usually assumed. For instance, you might think that consenting to space settlement where little is known about risks and their likelihoods is on a par with consenting to an experimental medical procedure. Since we can give unproblematic consent to experimental procedures, this means we should be capable of unproblematic consent to space settlement. But these cases aren’t perfectly analogous. The terminally ill patient has some shot at a better life by consenting to the experimental procedure. I presume that initial settlers would be rather affluent people who would be giving up an easy life to then live a life of considerable hardship. This would be the medical equivalent of a perfectly healthy person wishing to undergo an experiment procedure that would not only provide them with no medical benefit but would also make them much worse off. We ought to demand quite a lot from potential emigres before we accept their decision to instigate space settlement---at least more so than we demand from those consenting to experiment medical procedures.
Moderator: Excellent! Thank you all for your spirited participation, which I think has greatly clarified the issues and main lines of tension, making it easier for other researchers to take up the challenges we identify. Perhaps a quotation attributed to Enrico Fermi sums up what we have accomplished: “Before I came here I was confused about this subject. Having listened to your lecture I am still confused. But on a higher level.”
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