Living Computers

Alvis Brazma's book examines how life and information are bound together so tightly that they cannot be separated, and how that bond arose in the first place. Written in an approachable style, it follows life through the largest turning points in its evolution. It traces the history of biological information from chains of molecules in a world without life, to the first self-copying molecules, then through RNA and DNA, on to neural networks and animal brains. The story continues with human language and writing, the arrival of computer clouds, and a closing look toward a future no one can yet describe.

Brazma explains that every form of life known today is built from three kinds of molecules: proteins, which form the body's structure and carry out its work; DNA, which stores biological information; and RNA, which connects the two. Humans now record and process information in ways earlier life could not, yet Earth's DNA archive remains essential at this stage. Were that archive seriously damaged, all cultural knowledge and life itself would soon be lost.

The book raises a series of questions. Could a living organism be built from steel, rubber, copper and silicon rather than biological molecules? What was life like when it first appeared on Earth billions of years ago, and what might it be like millions or billions of years from now, if it still exists? Could future civilisations, including any descendants of our own, carry on without proteins, DNA and RNA? Brazma aims to give readers the background needed to consider such matters thoughtfully and with sound reasoning.

Written for students and researchers in physics, computing, biology, the social sciences and philosophy, the book also suits general readers curious about where life came from and where it is heading. Its central idea, that life can be understood as a computational phenomenon, should draw in anyone interested in our origins and future.