In the mid-19th century, American inventor Elias Howe was struggling to build a sewing machine. At the time, hand-stitching was all there was, so making clothes meant patiently sewing thread by thread.
After repeated failures, Howe dozed off one day. In his dream, he was wandering through a jungle when he was captured by natives and dragged before their king.
The king then told Howe: "I will run you through with a spear and kill you. But if you can build a machine that can sew within the next 24 hours, I will not only spare your life but also give you the princess as your wife."
Howe scrambled desperately to save his life, but he failed to build the machine before the deadline. At that moment, a soldier raised his spear to strike Howe. Then Howe saw the tip of the spear. Strangely, there was a hole in the spear's tip.
Another account holds that he witnessed the spear pierce through a tent and, as it withdrew, a strand of thread caught in the hole at the spear's tip and was pulled out.
When Howe woke up, he thought, "What a strange dream that was." But at that instant, a thought flashed through his mind.
"That's it! For sewing, the needle doesn't have to fully pass through the fabric. For sewing to work without passing through the fabric, the needle's eye must be at the tip of the needle."
Howe immediately rushed to his laboratory and made a needle in the shape of the spear he had seen in his dream. And so the sewing machine, one of history's great inventions, was completed.
August Kekulé was one of the founders of structural organic chemistry. He, too, made an important discovery through a dream.
After Kekulé dreamed in 1865 of a snake biting its own tail, he was able to imagine that the structure of the benzene molecule, a compound widely used in modern industry, would be ring-shaped.
Immersed in his research, Kekulé saw in a dream "large atoms forming chains, with small atoms attached to and moving at the ends of the chains." But he could not understand what it meant.
Then one day he had another dream. He was sitting and scribbling something in a textbook, but the work was making no progress. "I turned my chair toward the fireplace and dozed off. Again the atoms were gamboling before my eyes. This time the smaller groups kept modestly in the background. My mind's eye, rendered more acute by repeated visions of this kind, could now distinguish larger structures of manifold conformation. Long rows, sometimes more closely fitted together, all twining and twisting in snakelike motion. But look! What was that? One of the snakes had seized hold of its own tail, and the form whirled mockingly before my eyes."
Kekulé woke up as if struck by lightning. And once again he spent the whole night working out the consequences of the hypothesis.
Benzene is a cyclic molecule. It has a structure in which six carbon atoms form a hexagon, with a hydrogen atom attached at each corner. So remarkable was this discovery that the great organic chemist Adolf Baeyer said he would trade all the achievements of his lifetime for this discovery of Kekulé's.
In 1890, a ceremony was held to commemorate the 25th anniversary of Kekulé's discovery. Kekulé gave this advice to those attending the event: "Gentlemen, let us learn to dream, and then perhaps we shall find the truth."
For people with such determination, the sleeping brain becomes a laboratory. It continues working to solve problems that went unsolved during the day, even while asleep. I call this type of dream "researching dreams."
So when are such insights gained? One physicist told the German psychologist Wolfgang Köhler: "People often talk about the 3Bs. The great discoveries in science are made in three places—the Bus, the Bath, and the Bed."
The mathematician Henri Poincaré conceived the inspiration for a mathematical discovery the moment he stepped onto a step while changing buses. Archimedes, having gotten into a bathtub to bathe, saw the water overflow, realized the principle of buoyancy, and cried out "Eureka!" (meaning "I have found it"). The two cases of enlightenment gained through dreams in the third place, the bed, are as examined above.
What these three situations have in common is that the brain was not in a convergent state intensely focused on a problem, but in a free, divergent state temporarily removed from the task. I call this situation a "task-disengaged state."
The psychologist Michael Corballis described the state of having stray thoughts or being absent-minded as "mind-wandering" or a "wandering mind." In 2001, neuroscientist Marcus Raichle coined a term suited to this state. He called it the "default-mode network."
This refers to the connected state of the brain regions that are active when humans have stray thoughts. At this time, the frontal lobe, temporal lobe, and parietal lobe are known to be activated.
