Langdon nodded, incredulous.

This celebrated masterpiece was one of the signature works by French Postimpressionist Paul Gauguin—a groundbreaking painter who epitomized the Symbolist movement of the late 1800s and helped pave the way for modern art.

As Langdon moved toward the painting, he was immediately struck by how similar Gauguin’s palette was to that of the Casa Milà entryway—a blend of organic greens, browns, and blues—also depicting a very naturalistic scene.

Despite the intriguing collection of people and animals that appeared in Gauguin’s painting, Langdon’s gaze moved immediately to the upper-left-hand corner—to a bright yellow patch, on which was inscribed the title of this work.

Langdon read the words in disbelief: D’où Venons Nous / Que Sommes Nous / Où Allons Nous.

Where do we come from? What are we? Where are we going?

Langdon wondered if being confronted by these questions every day as he returned to his home had somehow helped inspire Edmond.

Ambra joined Langdon in front of the painting. “Edmond said he wanted to be motivated by these questions whenever he entered his home.”

Hard to miss, Langdon thought.

Seeing how prominently Edmond had displayed the masterpiece, Langdon wondered if perhaps the painting itself might hold some clue as to what Edmond had discovered. At first glance, the painting’s subject seemed far too primitive to hint at an advanced scientific discovery. Its broad uneven brushstrokes depicted a Tahitian jungle inhabited by an assortment of native Tahitians and animals.

Langdon knew the painting well, and as he recalled, Gauguin intended this work to be “read” from right to left—in the reverse direction from that of standard French text. And so Langdon’s eye quickly traced the familiar figures in reverse direction.

On the far right, a newborn baby slept on a boulder, representing life’s beginning. Where do we come from?

In the middle, an assortment of people of different ages carried out the daily activities of life. What are we?

And on the left, a decrepit old woman sat alone, deep in thought, seeming to ponder her own mortality. Where are we going?

Langdon was surprised that he hadn’t thought of this painting immediately when Edmond first described the focus of his discovery. What is our origin? What is our destiny?

Langdon eyed the other elements of the painting—dogs, cats, and birds, which seemed to be doing nothing in particular; a primitive goddess statue in the background; a mountain, twisting roots, and trees. And, of course, Gauguin’s famous “strange white bird,” which sat beside the elderly woman and, according to the artist, represented “the futility of words.”

Futile or not, Langdon thought, words are what we came here for. Preferably forty-seven characters’ worth.

For an instant, he wondered if the painting’s unusual title might relate directly to the forty-seven-letter password they were seeking, but a quick count in both French and English did not add up.

“Okay, we’re looking for a line of poetry,” Langdon said hopefully. “Edmond’s library is this way,” Ambra told him. She pointed to her left, down a wide corridor, which Langdon could see was appointed with elegant home furnishings that were interspersed with assorted Gaudí artifacts and displays.

Edmond lives in a museum? Langdon still couldn’t quite wrap his mind around it. The Casa Milà loft was not exactly the homiest place he had ever seen. Constructed entirely of stone and brick, it was essentially a continuous ribbed tunnel—a loop of 270 parabolic arches of varying heights, each about a yard apart. There were very few windows, and the atmosphere tasted dry and sterile, clearly heavily processed to protect the Gaudí artifacts.

“I’ll join you in a moment,” Langdon said. “First, I’m going to find Edmond’s restroom.”

Ambra glanced awkwardly back toward the entrance. “Edmond always asked me to use the lobby downstairs … he was mysteriously protective of this apartment’s private bathroom.”

“It’s a bachelor pad—his bathroom is probably a mess, and he was embarrassed.”

Ambra smiled. “Well, I think it’s that way.” She pointed in the opposite direction from the library, down a very dark tunnel.

“Thanks. I’ll be right back.”

Ambra headed off toward Edmond’s office, and Langdon went in the opposite direction, making his way down the narrow corridor—a dramatic tunnel of brick archways that reminded him of an underground grotto or medieval catacomb. Eerily, as he moved along the stone tunnel, banks of soft motion-sensitive lights illuminated at the base of each parabolic arch, lighting his way.

Langdon passed an elegant reading area, a small exercise area, and even a pantry, all interspersed with various display tables of Gaudí drawings, architectural sketches, and 3-D models of his projects.

When he passed an illuminated display table of biological artifacts, however, Langdon stopped short, surprised by the contents—a fossil of a prehistoric fish, an elegant nautilus shell, and a sinuous skeleton of a snake. For a passing moment, Langdon imagined Edmond must have mounted this scientific display himself—perhaps relating to his studies of the origins of life. Then Langdon saw the annotation on the case and realized that these artificts had belonged to Gaudí and echoed various architectural features of this home: the fish scales were the tiled patterns on the walls, the nautilus was the curling ramp into the garage, and the snake skeleton with its hundreds of closely spaced ribs was this very hallway.

Accompanying the display were the architect’s humble words: