The Great Blind Spot of Science and the Art of Asking the Complex Question the Only Answer to Which Is Life

At the heart of the book is the rigorous, passionate insistence that we need a softer and more elastic explanatory membrane between the three hard problems of reality: the hard problem of consciousness (rooted in the mystery of qualia, that inarticulable essence of what it feels like to be oneself, the felt interiority of being alive in a particular embodiment and enmindment), the hard problem of matter (the fact that everything observable arises from the interaction of particles and forces), and the hard problem of life (sculpted of information and an observer of information).

Biologists approach the problem by defining life in terms of observed features of life on Earth, which is not especially useful when you’re looking for life’s origins or for life elsewhere in the universe. Astrobiologists need guiding principles to inform how they conduct their search, but they, too, end up being overly anthropocentric in their reasoning: their search is most often directed at signs of life that would indicate biology exactly as we observe it here on Earth. Chemists either think life does not exist or that it is all chemistry (probably these are equivalent views). Computer scientists tend to focus too much on the software — the information processing and replicative abilities of life — and not enough on the hardware, i.e., the fact that life is a physical system that emerges from chemistry, and that the properties of chemistry literally matter. Physicists tend to focus too much on the physical — life is about thermodynamics and flows of energy and matter — and miss the informational and evolutionary aspects that seem to be the most distinctive features of the things we want to call life. Philosophers focus too much on the need for a definition or the flaws of providing one, and not enough on how we can move as a community beyond the definitional phase into a new paradigm. Nature does not share these boundaries between disciplines. They are artifacts of our human conception of nature, our need to classify things, and historical contingencies in how our understanding of the reality around us has evolved over the last few centuries. That is, they are the product of paradigms established in the past. We are in part pre-paradigmatic in understanding life as a general phenomenon in the universe because there is no defined discipline that can fully accommodate the intellectual discussion that needs to be had about what life is.

DNA cannot exist unless there is a physical system (e.g., a cell) with memory of the steps to assemble it. All objects that require information to specify their existence constitute “life.” Life is the high-dimensional combinatorial space of what is possible for our universe to build that can be selected to exist as finite, distinguishable physical objects. Being “alive,” by contrast, is the trajectories traced through that possibility space. The objects that life is made of and that it constructs exist along causal chains extended in time; these lineages of information propagating through matter are what it is to be “alive.” Lineages can assemble individual objects, like a computer, a cup, a cellular membrane, or you in this very instant, but it is the temporally extended structure that is alive. Even over your lifetime you are alive because you are constantly reconstructing yourself — what persists is the informational pattern over time, not the matter.

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The fundamental unit of life is not the cell, nor the individual, but the lineage of information propagating across space and time. The branching pattern at the tips of this structure is what is alive now, and it is what is constructing the future on this planet.

Pair with the of Sara Imari Walker on the Lex Fridman pocast and Making Sense podcast