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How Mendeleev Invented His Periodic Table in a Dream

“Awakening, I immediately wrote it down on a piece of paper.”

How Mendeleev Invented His Periodic Table in a Dream

Trailblazing chemist Dmitri Mendeleev (February 8, 1834–February 2, 1907) came to scientific greatness via an unlikely path, overcoming towering odds to create the periodic table foundational to our understanding of chemistry. Born in Siberia as one of anywhere between 11 and 17 children — biographical accounts differ, as infant mortality rate in the era was devastatingly high — he was immersed in tragedy from an early age. His father was a professor of fine arts, philosophy, and politics, but grew blind and lost his teaching position. His mother became the sole breadwinner, working at a glass factory. When Dmitri was thirteen, his father died. Two years later, a fire destroyed the glass factory.

The following year, determined to ensure her son’s education, his mother took him across the country hoping to get him into a good university. The University of Moscow rejected him. At last, they made it to Saint Petersburg, Russia’s then-capital. Saint Petersburg University — his father’s alma mater and, incidentally, both of my parents’ — admitted him and the family relocated there despite their poverty.

A promising scholar, Mendeleev — also spelled Mendeleyev in English — published papers by the time he was 20 and attended the world’s first chemistry conference at 26. By his mid-thirties, he was intensely preoccupied with classifying the 56 elements known by that point. He struggled to find an underlying principle that would organize them according to sets of similar properties and eventually reaped the benefits of the pattern-recognition that fuels creativity.


But rather than by willful effort, he arrived at his creative breakthrough by the unconscious product of what T.S. Eliot called idea-incubation — one February evening, after a wearying day of work, Mendeleev envisioned his periodic table in a dream.

In Mendeleyev’s Dream: The Quest for the Elements (public library), novelist Paul Strathern reconstructs the landmark moment from the scientist’s letters and diaries, and reimagines it with a dose of satisfying literary flourishing:

As Mendeleyev’s eyes ran once more along the line of ascending atomic weights, he suddenly noticed something that quickened his pulse. Certain similar properties seemed to repeat in the elements, at what appeared to be regular numerical intervals. Here was something! But what? A few of the intervals began with a certain regularity, but then the pattern just seemed to peter out. Despite this, Mendeleyev soon became convinced that he was on the brink of a major breakthrough. There was a definite pattern there somewhere, but he just couldn’t quite grasp it… Momentarily overcome by exhaustion, Mendeleyev leaned forward, resting his shaggy head on his arms. Almost immediately he fell asleep, and had a dream.

The dream, of course, was just a function of what the human brain normally does during sleep — organizing and consolidating the ideas, images, and bits of information that occupy our waking hours. And what Mendeleev’s waking mind was so vigorously occupied with was the quest for a classification system that would order the elements. “It’s all formed in my head,” he lamented, “but I can’t express it.” It was only when he reentered his own head under the spell of sleep’s uninhibited state that the disjointed bits fell into a pattern and the larger idea expressed itself.

Mendeleev himself would recount in his diary:

I saw in a dream a table where all the elements fell into place as required. Awakening, I immediately wrote it down on a piece of paper.

Mendeleev's 1869 handwritten draft of the periodic table
Mendeleev’s 1869 handwritten draft of the periodic table

Complement Mendeleyev’s Dream with Margaret Mead’s existentially revelatory dream about the meaning of life and John Steinbeck’s prophetic dream about how the commercial media are killing creative culture, then revisit the science of what the brain actually does while we sleep.

Published February 8, 2016




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