Humanity on a Tightrope: Thoughts on Empathy, Family, and Big Changes for a Viable Future, written by biologist and environmentalist Paul Ehrlich and psychologist Robert Ornstein, is a short book about the need to expand our sense of empathy and in-group identification to all of humanity. Unlike virtually all contemporary books on sociopolitical and environmental topics, it explicitly discusses global government.

Empathy is the ability to understand another person’s feelings and experiences on an emotional level; unlike sympathy, it does not require believing those feelings to be justified. Throughout the book, the authors place our both capacity for empathy and our destructive tendency to define in-groups and out-groups on its evolutionary foundation. We evolved as small-group creatures who knew all the members of our tribe — basically an extended family — and only rarely encountered strangers. Cooperation within these groups, particularly with regards to child care, was likely key to our survival and success, but there was little need to extend our well-developed empathetic abilities to non-kin.

All this changed once agriculture and civilization appeared. Now, humans lived in comparatively large social groups, many of whose members they did not know. So they conceptualized fellow members of these groups as pseudo-kin. Modern examples of this phenomenon range from the Brotherhood of Teamsters to the practice of addressing Catholic priests as “Father” and the use of words like “motherland”. Phrases like “human family” and “the family of man” follow the same pattern. Of course, this level of pseudo-kinship (which is actually less abstract than many of the social groups constructed on the “family” metaphor) is just beginning to take root in the minds of a substantial fraction of the world’s population.

After laying out this history, Ehrlich and Ornstein go on to discuss a few ways we might come to see each other as more alike and thus “one of us”. These range from electronic communication and educational practices to soap operas with a message. This part of the book would have benefited from more discussion of how people come to emotionally identify with large, abstract groups like nation-states and how those of us who already consider ourselves world citizens got to be that way. (A remarkable cross-cultural study published in 2010 that found that people who lived in market-dependent societies were more likely to treat strangers fairly in an experiment comes to mind.) The authors also mention how interaction between people helps them identify with each other. With this in mind, I wonder about how to maintain global connectivity as fossil fuels run out and climate disruption makes their continued use suicidal anyway. Should jet fuel or the right to burn it be preferentially allocated to long-distance flights, where airplanes cannot be easily replaced by trains? Economic localization is fashionable among environmentalists these days and sometimes it undoubtedly makes sense, but would a localized world be a more warlike world?

A world government would certainly eliminate this problem — not by ending human conflicts but by keeping people from raising armies and going to war over those conflicts — and from a world federalist perspective, the most remarkable feature of _Humanity on a Tightrope_ is the way Ehrlich and Ornstein talk about global government. A few quotes: “At the extreme of family structure questions is how more than seven billion people should organize themselves into a single entity to solve massive global problems. That is, how should we unite the nation-states?” (p. 98) “Needless to say, the world of Rush Limbaughs and Mahmoud Ahmadinejads hardly seems ready for a global government of any sort, or more global influence in national affairs, which seems more likely, any more than European nations and their colonies seemed ready for democracy in 1700.” (p. 100, emphasis mine) The book also discusses the Federalist – anti-Federalist debate in American history, refers readers to and encourages them to support the world government movement.

While overly meandering at times, this book covers much ground in only 130 pages. It is very much worth reading, and the remarkable annotated bibliography in the appendix may itself be worth the purchase price. If Humanity on a Tightrope gets more environmentalists to think in terms of our common human identity and maybe even return the question of the desirability of something like a Federal Republic of Earth to the public discourse, it will have accomplished much of lasting value.