Rosalind Franklin

How they reason

Thinking

Let the spots on the photograph decide

Aphorism

Principle

I announced the death of the helical A-DNA

When an asymmetrical A-DNA image in May 1952 contradicted the accepted helix, I followed the data, and marked it with a mock funeral notice for the "crystalline" helix.

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Principle

Build the model only after the data constrain it

I held that model building in structural science should start only once enough of the structure is known from experiment. Two failed triple-helix DNA models bore that out.

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Reflection

Paris trained me as an X-ray crystallographer

In 1947 I joined Jacques Mering's laboratory in Paris, where I learned to apply X-ray diffraction to amorphous, disordered substances such as carbon — the skill my later research relied on.

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Go deeper

Insight timeline

How the thinking unfolded over time.