METI or REGRETTI

This chapter assesses the ethical justification for attempting to message extraterrestrial intelligence (METI). Most of the discussion within the space community concerning METI has been about the level of risk it poses. Addressing the empirical dimensions of METI risk is a useful exercise, to be sure, but it is often unappreciated that these details just do not resolve key questions. In particular, if one looks at METI through an ethical lens, the central question is not what the level of risk is but whether those who are exposed to that risk agree to it. Rather than simply allowing anyone with access to the necessary resources do whatever they wish, people need to involve public policy, social science, humanities, and other fields of expertise to develop explicit best practices and then work to enshrine these in soft law.

What Are Extremophiles?

This chapter studies the concept of an extremophile. In the 1970s, R. D. MacElroy coined the term “extremophile” to describe microorganisms that thrive under extreme conditions. This hybrid word transliterates to “love of extremes” and has been studied as a straightforward concept ever since. The chapter then delineates five different ways to think about extremophiles, concluding that the concept is especially prone to the vagueness and arbitrariness that plague other biological categories, since it unavoidably involves debatable assumptions about life's nature and limits. These five concepts are, briefly, human-centric, at the edge of life's habitation of morphospace, by appeal to statistical rarity, described by objective limits, and at the limits of impossibility for metabolic processes. Importantly, these concepts have coexisted, unacknowledged and conflated, for decades. Confusion threatens to follow from the wildly varied inclusion or exclusion of organisms as extremophiles depending on the concept used. Under some conceptions, entire kinds of extremophiles become meaningless. Ultimately, since people's understanding of how life works is shaped by what people take to be its extremes, clarifying extremophily is key for many large-scale projects in biology, biotechnology, and astrobiology.

Life as It Could Be

This chapter explores the intersection between two related fields: synthetic biology and astrobiology. Pushing the engineering of life past traditional limits in molecular biology and expanding the envelope of life to forms never before extant, synthetic biologists are now beginning to design experimental ways of getting at what astrobiologists have long suspected: that the life known here on Earth is but a subset of vast combinatorial possibilities in the universe. The resonances between the future engineered possibilities of this world and speculations about possible biologies on habitable others are not merely happenstance. Indeed, there is a curious and compelling deeper history interlinking scientific speculation about new forms of life elsewhere in the universe with visions for the human-directed engineering of new forms of life on Earth. For decades, the astrobiological and the synthetic biological have mutually inspired each other and overlapped in powerful genealogical ways.

Three Lives and Astrobiology

This chapter explores the concept of life across traditions, from science to philosophy to theology. The term “life” covers at least three constellations of meaning or life-concepts: biological life, internal life, and rational life. Biological life shares traits with all cellular life on Earth (archaea, eubacteria, and eukarya). Internal or conscious life shares subjective interiority with humans. Rational life shares intellect with all minds that can distinguish truth from non-truth. These three lives possess different origins, extents, and futures. The chapter then identifies three distinct “hard problems of life” relating to the origin and extent of biological organization, consciousness, and reason: moving from non-life to life, from life to sentience, and from sentience to rationality. The Drake equation, the Fermi paradox, and the anthropic principle provide concrete examples in astrobiology.

Myth-Free Space Advocacy Part IV

This chapter addresses a sociological question that has largely been ignored: How much does the public care about life in space? It argues that there is no clear evidence of widespread support in the United States for the scientific search for extraterrestrial life. First, a comparison with U.S. views on evolution suggests that many religious individuals would be opposed to the search. Second, a comparison with U.S. views on space exploration suggests that a large majority of the public would be unwilling to support increased funding for the search. Finally, a review of existing surveys on the public's views about astrobiology suggests that little is known about how the public frames the search for extraterrestrial life. This makes it difficult to draw any decisive conclusions about the purported universal appeal of astrobiology.

Convergences in the Ethics of Space Exploration

This chapter outlines the ethical frameworks provided by some of the leading figures in the contemporary debate on space exploration, identifying resonances between their views and traditional concepts in ethical philosophy such as natural law and virtue theory. One of the first deep similarities apparent to the ethical frameworks of these leading figures is that, to a certain extent, living things should just be left to be—that is, not meddled with, allowed to pursue their own ends. The second deep similarity between these ethics is that sometimes one ought to help things grow. As a third deep similarity is all of these ethics issues acknowledge that problems appear when one organism’s natural goals conflict with those of another organism. This, then, promotes the idea that one should avoid conflicts that harm other living things. Ultimately, despite their differences, these ethics converge on a broadly applicable ethical framework: protect alien life in proportion to its capacity for excellence.

Meaning of the Living State

This chapter draws inspiration from statistical physics to describe a statistical category that can be termed the “living state.” References to a living state can be found throughout origin of life and astrobiology science. Some researchers have used the concept of the living state to explicitly place biological phenomena within the epistemological scope of statistical physics. Within this framework, biological phenomena at a given scale of organization are explained and understood by appealing to the statistical properties of the dynamics of the smaller and larger scales. This is analogous to how distinct states of matter are understood by appealing to the statistical properties of atoms, with the important distinction that statistical physicists have historically not included constraints from larger levels of organization, which are essential in determining the properties of living systems. This conception of the living state may enable astrobiologists to integrate progress from different disciplinary perspectives into a quantitative theory of life.

To the Humanities and Beyond

This introductory chapter provides an overview of the exploration of astrobiology. While new, astrobiology's recent success has been nothing short of amazing. In just the past 25 years, scientists have learned that the building blocks of life are found basically everywhere in the universe; that getting these building blocks to engage in the kinds of complex chemistry people associate with life is far easier than people used to think; and that planets where life could potentially evolve are extremely common. Nevertheless, scientists from a variety of fields are just beginning to address the many questions raised by the real possibility of life on other planets. Relatively little research on the broader social and conceptual aspects of astrobiology has been undertaken by scholars outside the small community of space scientists. However, a fertile field awaits early adopters from other disciplines, with many profound and largely unexplored questions waiting to be addressed by relevant experts. Some of these research questions fall squarely within traditional humanities, while others span the boundary between empirical science and other fields.

Earth, Life, Space

This chapter discusses how the scientific search for evidence of extraterrestrial life has affected people's conception of the terrestrial biosphere. Austrian geologist Eduard Suess originated the term “biosphere” in 1875, describing Earth's biosphere as the area of the planet that supports life. With a deeper understanding of the history and nature of the terrestrial biosphere, the community of scientists engaged in space science and exploration recognizes the possibility of other biospheres beyond Earth. As a result, the quest to find evidence of extraterrestrial life has affected people's conception of the biosphere, the way they think about their home planet and their place on it, and their perspective on the possibility of extraterrestrial biospheres nearby and far away. Indeed, astrobiology, planetary exploration, and exoplanet science have made significant contributions to this changing understanding.

Rethinking Conceptual Intelligence and the Astrobiology Debate

This chapter addresses the implications of people’s understanding of conceptual intelligence on extraterrestrial debates in astrobiology. In presupposing life, and by extension conceptual intelligence, is so fine-tuned as to be unique to this planet creates an equivocation that opens up scientific claims to ineradicable skepticism. It is one thing to be doubtful about whether life exists elsewhere, if that life is intelligent, or even if humans will ever find it. This is to be expected and healthy. However, it is quite another to assume that all expressions of intelligence on this planet are the direct product of natural processes unique to Earth. If all forms of intelligence are ultimately rooted in local expressions of biological utility, then the necessity and universality that anchors scientific explanations can be no more than complicated ways of registering people’s own interspecies agreement on things and thus of no help in critically investigating the larger structure of the natural universe with some measure of objectivity.