“Gary Tomlinson has long been one of the most inventive interpreters of the dialogue between the natural sciences and the humanities, and in Astrosemiosis he takes up one of the most pressing questions: how life becomes capable of meaning. At a moment when intelligence is increasingly attributed to everything from microbes to machines, Tomlinson offers a rigorous and timely account of what meaning- making actually entails. Combining philosophical depth with environ-mental history and semiotics, Astrosemiosis rethinks life, signs, and intelligence as planetary processes, making it essential reading for anyone interested in what it means to be alive.”
— Alfredo Thiermann, Professor of History and Theories of Archi tecture, Technology, and Media, Swiss Federal Technology Institute of Lausanne

“This book is a bold and stimulating attempt to connect astrobiology and semiotics, two fields much concerned with signs, signals and signatures. Tomlinson offers astrobiologists a new conception of what makes some forms of life special: the capacity to make and use meaningful signs. Was the evolution of this capacity one of the ‘major transitions’ that profoundly altered the course of Earth’s evolutionary history? Can the study of sign-making in non-human animals (birds, whales, and apes for example) helpfully reframe the search for extraterrestrial intelligence? How widespread and various might ‘signworlds’ be among alien biospheres? In how many different ways might the cognitive circuitry necessary for sign- making be realized? Such are the compelling interdisciplinary questions at the heart of this book. Although highly original, Tomlin-son’s book can be seen as a contribution to two broad movements in contemporary scholarship: first, the rise of planetary and indeed interplanetary thinking in the arts, humanities, and social sciences and, second, the increasing role and stature of philosophical and conceptual work in astrobiology, the science of life in the universe.” — Sean McMahon, Professor of Astrobiology, University of Edinburgh “

Gary Tomlinson is our most important living semiotician. Astrosemiosis uses the expanse of the cosmos and the range of science fiction to create a universal doctrine of signs for any possible world. It is academic appointment reading.”
— Leif Weatherby, Professor of German, New York UniversityGary

★Breaking the bounds of single-discipline research, the author brings astronomical inquiries into profound humanistic and philosophical reflection. As Sterling Professor at Yale University and a MacArthur Fellow, he stands as a powerful guarantee of intellectual depth and rigorous scholarship.
★The search for extraterrestrial intelligence (SETI) has long been dominated by astronomers and biologists. This book pioneers a new humanistic approach centered on semiosis and meaning-making. Integrating evolutionary science and information theory, it derives the semiotic constraints required for the emergence of advanced cosmic intelligence.
★Meticulously reasoned, this essential read for science enthusiasts uses Earth’s living semiotic systems as a reference to calculate the likelihood of such traits evolving within biospheres on other planets. It explores an age-old, ultimate question: if advanced extraterrestrial civilizations exist in the cosmos, what underlying logic shapes their thought, technology, language and culture?

A voyage into the mysterious world of alien intelligence

Do advanced life forms exist beyond Earth? Is there intelligent life elsewhere in the cosmos? Ask an astrobiologist and you will usually get back a qualified "yes," but further investigation is stymied by the slipperiness of concepts like "advanced" and "intelligent." Most astrobiologists then turn their attention to more tractable scientific issues, examining geological and biological conditions for life on Earth in order to propose how it might have arisen elsewhere. Their ambition is to understand life wherever it occurs as part of the processes of planetary formation and change.
Gary Tomlinson extends this scientific project as only a humanist can. Starting from the foundation of earthly meaning, sign making or semiosis, he opens a new path toward the alluring question of alien intelligence. He joins evolutionary science, information theory, and a theory of the constraints under which signs occur to delimit the grounds for the emergence of meaning-making life forms anywhere. Astrosemiosis identifies evolved features on earth plausibly required to meet semiotic constraints and gauges the likelihood that analogous features would evolve in extraterrestrial biospheres. Rethinking sign making as a planetary process, it narrows the gap between speculation on smart aliens and empirical astrobiological science.

Gary Tomlinson is Sterling Professor of Music and Humanities at Yale University and the recipient of a MacArthur "genius" award. His recent research sits at the intersection of music, evolutionary theory, and philosophies of signs and meaning. In his earlier Zone books he set new terms for the question of how humans come to be musical creatures (A Million Years of Music, 2015) and explored the reach of meaning-making beyond humans in our world (The Machines of Evolution and the Scope of Meaning, 2023).