Why do we so easily believe everything about us—our intelligence, moods, and learning styles—is written in our genes?

It’s not a foolish belief. We see the evidence all around us.
Children inherit their parents’ eye colour.

Tall parents often have tall children.

Hair texture, skin tone, facial features — these traits flow down family lines like heirlooms.

It feels obvious. Our bodies, and by extension, our minds, must express a blueprint written at conception.

The giants of early science reinforced this view.

Charles Darwin had shown that species change through variation and selection.

Gregor Mendel, carefully crossing peas in a monastery garden, uncovered the hidden laws of inheritance: dominant and recessive traits, predictable ratios, and clear outcomes.

It was a triumph of clarity — and it was only natural that this triumph would expand.
If eye colour were inherited, surely attention span must be too.

If height was largely predetermined, so were ambition, creativity, and anxiety.

Then came the crowning achievement: in 1953, at Cambridge, James Watson and Francis Crick unravelled the structure of DNA.

The double helix: two twisting ribbons, wound around each other, encoding life in sequences of four simple molecules.

DNA made RNA. RNA made proteins. Proteins built cells. Cells built bodies.

It was simple.

It was beautiful.

Science had cracked the code of life.

Or so it seemed.

Even today, we speak about inheritance with affection and certainty.

A boy who possesses his father’s stubbornness or his mother’s smile is called “a chip off the old block.”

A girl who reflects her grandfather’s musicality or her grandmother’s fierce independence draws knowing nods: “The apple doesn’t fall far from the tree.”

The phrases are comforting because they…