The Gene Prophet: How Erwin Schrödinger's "What Is Life?" Revolutionized Biology

The story of how a physicist's question inspired a biological revolution and paved the way for the discovery of DNA

Erwin Schrödinger

Nobel Prize-winning Physicist

The Physicist Who Asked a Biologist's Question

In February 1943, amidst the turmoil of World War II, Nobel Prize-winning physicist Erwin Schrödinger stepped onto the stage at Trinity College, Dublin, to deliver a series of public lectures on an unexpected topic for a physicist: the fundamental nature of life⁴ .

The Central Question

Schrödinger posed a deceptively simple question: "how can the events in space and time which take place within the spatial boundary of a living organism be accounted for by physics and chemistry?"² .

Prescient Insights

At a time when genes were abstract concepts with no known physical basis, this physicist from another field offered breathtakingly prescient insights that would inspire the founders of molecular biology¹ ⁴ .

1943

Schrödinger delivers his landmark lectures at Trinity College, Dublin⁴ .

1944

"What Is Life?" is published, becoming one of the most influential scientific writings of the 20th century¹ .

1953

Watson and Crick discover the DNA double helix, inspired by Schrödinger's ideas² .

The Aperiodic Crystal: Schrödinger's Conceptual Masterstroke

At the heart of Schrödinger's book lay a brilliant theoretical leap. He proposed that genetic information must be stored in what he called an "aperiodic solid" or "aperiodic crystal" that contained a "code-script" determining "the entire pattern of the individual's future development and of its functioning in the mature state"⁴ ⁷ .

This conceptual breakthrough contained two crucial insights that would prove remarkably accurate.

Molecular Stability

Schrödinger recognized that hereditary material must possess both the stability of a crystal and the complexity to carry information² .

Information Storage

Unlike a periodic crystal with repeating patterns, Schrödinger's proposed "aperiodic crystal" could contain vast amounts of information² .

Key Concepts in Schrödinger's "What Is Life?" (1944)

Concept	Schrödinger's Description	Modern Equivalent
Aperiodic Crystal	A stable but non-repeating molecular structure that stores information	DNA molecule
Code-Script	The configuration of covalent chemical bonds that contains genetic information	Genetic code (DNA sequence)
Order-from-Order	The principle that life maintains and transmits structure	Biological inheritance
Negative Entropy	How living systems maintain order by exporting disorder	Metabolic energy utilization

The Genetic Code-Script: From Metaphor to Reality

Perhaps Schrödinger's most enduring linguistic contribution was his introduction of the term "code-script" to describe how genetic information is stored and transmitted⁴ .

Code-Script Metaphor

This powerful metaphor would eventually transform how scientists thought about heredity, even though his precise meaning differed somewhat from our modern understanding of the genetic code.

Thermodynamic Paradox

Schrödinger brilliantly explained that living organisms maintain their highly ordered state by exporting entropy to their environment² .

Philosophical Musings

The book's impact extended beyond pure science to philosophy, with Schrödinger grappling with consciousness, determinism, and free will² ⁷ .

Influence on Key Scientists

James Watson

"Schrödinger's book suggested that genes could be thought of as the key components of living cells and that it was important to determine the structure of genes"⁴ .

Francis Crick

Both Watson and Crick independently acknowledged that Schrödinger's book inspired their initial research² .

The Experimental Revolution: Putting Schrödinger's Ideas to the Test

While Schrödinger's book was theoretical, its greatest legacy lies in how it inspired experimental scientists to uncover the physical basis of life.

The Miller-Urey Experimental Setup

Component	Simulated Natural Element	Experimental Implementation
Gas Mixture	Early Earth's reducing atmosphere	Methane, ammonia, hydrogen in 2:2:1 ratio
Energy Source	Atmospheric lightning	Continuous electrical spark between electrodes
Water Cycle	Primordial oceans	500-mL flask half-full of boiled water
Condensation	Rainfall	Condenser cooling gas back into liquid

Organic Molecules Detected in Miller-Urey Experiment

Time Period	Analytical Method	Number of Amino Acids Identified	Key Examples
Original 1953 analysis	Paper chromatography	5	Glycine, α-alanine, β-alanine
Early 1970s reanalysis	Improved chromatography	33	Multiple proteinogenic amino acids
21st century reanalysis	Modern analytical equipment	20+	Various biological and non-biological amino acids

The Scientist's Toolkit: Essential Reagents in Origin of Life Research

Nucleic Acid Reagents

DNA and RNA extraction kits, PCR components⁶

Enzymes and Proteins

DNA polymerases, restriction enzymes⁶

Chromatography Reagents

For separation and identification of organic molecules⁶

Cell Culture Reagents

Media, growth factors, supplements⁶

Schrödinger's Enduring Legacy: From 1944 to the Future of Biology

The influence of What Is Life? has stretched far beyond its initial publication. As Roger Penrose noted, it remains "among the most influential scientific writings of the 20th century"¹ .

Bridging Disciplines

The book successfully bridged physics and biology, introducing concepts like information storage and processing that would become fundamental to molecular biology⁴ ⁷ .

It demonstrated how a brilliant mind from one discipline could ask transformative questions in another.

Inspiring Future Research

Schrödinger's book inspired a generation of scientists to look for the physical basis of life—a search that continues today in fields as diverse as:

Synthetic biology
Astrobiology
Artificial life research

The Enduring Question

His central question—"What is life?"—remains as compelling and urgent as ever, driving us to understand our place in the natural world and the fundamental principles that distinguish the living from the non-living.

As we continue to unravel the mysteries of the genetic code, create artificial life in laboratories, and search for life beyond Earth, we walk a path that was significantly shaped by a physicist who dared to ask a biologist's question in a Dublin lecture hall eight decades ago.