PASTCF President’s Column February 2023
Recently, I have run into several instances where people are wondering about life elsewhere in the universe. And I don’t mean reports that Google’s AI engine thought that JWST had seen the first extrasolar planet. I mean consideration of the question in a much more thoughtful way. The concluding bottom line is that, no matter what question is asked about extraterrestrial life in the universe, the answer is: we don’t know. If you want to cast that in spiritual terms, one could say that the universe as it was created should fill us with humility and awe. I will return to this at the end.
The obvious initial questions are: what would such life forms look like, what would they be based on, would they be intelligent, would they be benevolent? But when one starts contemplating such issues, much more fundamental questions arise: what defines “life”, “intelligence”, how does life get started, what exactly is consciousness and how did it come about, what about self-consciousness? It turns out that these questions are really hard to answer in a meaningful way. One of the basic attempts at defining life turns on metabolism: an entity that takes energy from its surroundings to feed and support itself in a sustainable fashion. One should probably add to that the notion of self-preservation and procreation. That might help to render the evolution of terrestrial life forms plausible, even the transition from cellular to multi-cellular, but we still get stuck when faced with the mystery of consciousness.
Does life depend on evolutionary principles? Yes, that is probably the case, but it seems presumptuous to assume that it needs to depend on DNA. Just like there has been speculation for a long time on whether life could be silicon-, rather than carbon-, based. The simple answer “you will recognize life when you see it” is probably not correct. We might not recognize life when we see it. The February 2023 issue of Scientific American carries an article by Sarah Scoles on the subject. A major focus of that article is on the Laboratory for Agnostic Biosignatures (LAB); its principal investigator works at Goddard Space Flight Center. Call it the search for LAWDKI — Life As We Don’t Know It. The initial reaction to “how do we detect life on an exoplanet” is “look for oxygen in the atmosphere”. Well, that is awfully terracentric. One needs to cast the net wider.
There is a delightful book by Arik Kershenbaum: “The Zoologist’s Guide to the Galaxy: what animals on earth reveal about aliens — and ourselves”. He tries to extract from what we know about terrestrial life forms and their evolution the essential rules that have driven the development of life on earth and considers them on their universal validity. It is insightful and revealing in pointing to how we might want to look for, and at, extraterrestrial life forms.
But there is not only the question what life might look like in other places in the universe. There is also the question how it might change and look like over time, especially time scales significantly longer than human generations. Our earth has been around for some 5 billion years and its face and life forms have changed drastically over that period. Earth still has another 5 billion years, or so, to go, so we may expect even more drastic changes, especially since humanity has had a rather heavy hand, exponentially, in shaping the terrestrial environment over the past few millennia and particularly the last century. How far can we extrapolate the development of life on earth? Maybe not for more than one human generation.
Christopher Mason, in “The Next 500 Years: Engineering Life to Reach New Worlds” makes an attempt for the long term, but admits to its shortcomings. His intention is mainly to get the conversation going, as humanity, at some point in the future, needs to start looking for resources (or a home) beyond the solar system: the sun and the earth won’t be here forever — if we manage not to drive ourselves to extinction, a prospect which should not be dismissed.
Sir Martin Rees, in “On the Future: Prospects for Humanity”, considers a post-humanity future possible where organic life will be dominated by electronic life forms. There is a lot that can happen in the next 5 billion years — and even much more after that until the point where everything in the universe dies a cold dark death. So far, I have pointed out that there is an awful lot we don’t know and probably more that we cannot even imagine. But at some point we may need to consider the question what to do with extraterrestrial life when we encounter it. And here we come to an ethical, and possibly a theological, issue. The first reaction of enlightened people is probably that we should respect alien life forms and that “Thou shalt not kill” also applies to them. But maybe we should not be so hasty. I am a longtime member of the Fellowship Of Reconciliation and consider myself a pacifist. But I have no problems killing plants for food, or pesky insects or nasty viruses; and I do eat meat. How would I react to intelligent electronic beings or LAWDKI creatures that exude toxins or have nefarious designs on humans? Food for thought.
