How Life Works

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Drawing on recent discoveries and insights, How Life Works outlines a new vision of our understanding of life for the 21st century.

Philip Ball is a freelance writer and broadcaster whose many books on the interactions of the sciences, the arts, and the wider culture include Bright Earth, Curiosity, Patterns in Nature, How to Grow a Human, The Modern Myths, The Elements, and, most recently, The Book of Minds, all also published by the University of Chicago Press. His book Critical Mass won the 2005 Aventis Prize for Science Books. Ball is also the 2022 recipient of the Royal Society’s Wilkins-Bernal-Medawar Medal for contributions to the history, philosophy, or social roles of science. He trained as a chemist at the University of Oxford and as a physicist at the University of Bristol, and he was an editor at Nature for more than twenty years. He lives in London.

All the same, I believe we can do better. I will show how research in molecular and cell biology over the past several years has painted a richer and much more astonishing picture than that bleak and obsolete mechanical metaphor. The picture does at times appear fantastically baroque and perplexing, but in the end it takes the burden of control off the shoulders of the genome, relying instead on principles and processes of self-organization that, precisely because they have no need of tight genetic guidance, avoid the fragility that would engender. I must stress that there is nothing in this new view that conflicts with the neo-Darwinian idea that evolution shapes us and all other organisms and that it depends on the genetic transmission of information between parent and offspring. However, in this new view genes are not selfish and authoritarian dictators. They don’t possess any real agency at all, for they can accomplish nothing alone and lack a capacity for making decisions. They are servants, not masters.
Fundamentally, this new view of biology—which is by no means complete, and indeed is still only nascent—depends on a kind of trust. You could say that genes are able to trust that there are processes beyond their capacity to directly control that will nonetheless allow organisms to grow and thrive and evolve. (Biologists need to develop that trust too.) This way of working appears repeatedly in biology when things get complicated and tasks get hard. When organisms first became multicellular, when they became able to adjust to and exploit the full richness of their surroundings through sensory modalities like vision and smell, when their sensitivity and receptivity to the environment became genuine cognition, it seems that life increasingly relinquished a strategy of prescribing the response of the organism to every stimulus, and instead supplied the basic ingredients for systems that could devise and improvise solutions to living that are emergent, versatile, adaptive, and robust.
The new picture dispels the long-standing idea that living systems must be regarded as machines. There never has been a machine made by humankind that works as cells do. This is not to deny that living things are ultimately made of insensate and indeed inanimate molecules: we need no recourse to the old idea of vitalism, which posited that some fundamental and mysterious force made the difference between living and inert matter. Yet dispensing with the machine view of life allows us to see what it really is that distinguishes it from the inanimate world. The distinction is as fundamental and wondrous as the formation of the universe itself—but more amenable to scientific study, and for that reason probably more tractable.
In particular, life is not to be equated with that special kind of machine, the computer. It is certainly true that life performs kinds of computation, and indeed there are key features of biology that can be fairly well understood using the theory of information developed to describe modern information technologies. What is more, a comparison with machines can sometimes be a useful way of thinking about how parts of the process that is life operates. I will occasionally make such parallels. It is meaningful to say that our cells possess pumps, motors, sensors, storage, and readout devices. That, however, is very different from the modern trend of discussing the fundamental features of living organisms by comparing them to electrical circuits, computers, or factories. No computer today works as cells do, and it is far from clear that they ever will (or that this would be a good way to make a computer anyway). There is so far no technological artifact that provides a good analogy for living systems. These are a different kind of entity, with their own logic, and they have to be their own metaphor.
 

Prologue
Chapter 1. The End of the Machine: A New View of Life
Chapter 2. Genes: What DNA Really Does
Chapter 3. RNA and Transcription: Reading the Message
Chapter 4. Proteins: Structure and Unstructure
Chapter 5. Networks: The Webs That Make Us
Chapter 6. Cells: Decisions, Decisions
Chapter 7. Tissues: How to Build, When to Stop
Chapter 8. Bodies: Uncovering the Pattern
Chapter 9. Agency: How Life Gets Goals and Purposes
Chapter 10. Troubleshooting: Rethinking Medicine
Chapter 11. Making and Hacking: Redesigning Life
Epilogue
Acknowledgments
Source Notes
Bibliography
Index