LUCK ISN’T SO DUMB AFTER ALL: I’ve been enjoying reading about the science of lucky breaks, as explored by Janice Kaplan and Barnaby March in How Luck Happens. They take a critical look at some of the legends of luck, like the story of Alexander Fleming’s discovery of penicillin when he came from vacation to find that a petri dish he’d left on a windowsill had been contaminated with mold:

And lo and behold, the bacteria surrounding the mold had been destroyed.

He didn’t shout, “Eureka!” or go running naked through the streets (as Archimedes reportedly once did),* but he did realize that the mold might have inhibited the bacterial growth. And there you have it— one lucky break and millions of people have been saved from diseases like strep throat and scarlet fever, as well as wound infections.

“When I woke up just after dawn on September 28, 1928, I certainly didn’t plan to revolutionize all medicine by discovering the world’s first antibiotic, or bacteria killer. But I suppose that was exactly what I did,” Fleming said later.

The revolution wasn’t quite as casual as all that. During World War I, Fleming had been in the Royal Army Medical Corps doing research into wound infections and antiseptics. After the war, he returned to his lab at St. Mary’s Hospital at the University of London, and by 1921, he had made his first big discovery, finding an enzyme that fights bacteria.

That research reportedly began when Fleming had a cold and dropped some mucus into one of his bacteria cultures. Are you starting to see a pattern here? The dropped mucus and the plopped mold were serendipitous, but they were common events. It wasn’t their occurrence that was so lucky and magical, but what Fleming made of them.

At the time of his family vacation, Fleming had been working on questions about bacteria and the human immune system for more than a decade. As is often the case in science, he had many small breakthroughs and lots of incremental steps. Many of the things he tried didn’t lead anywhere. When one does pay off, it’s not random luck— it’s the result of months and years of focused energy, and plenty of experiments that didn’t pan out.

You get lucky only when you know what you’re looking for. Someone else coming into Fleming’s lab after that vacation might have tossed away the contaminated petri dish without a second thought. One man’s scientific breakthrough is another man’s yucky, moldy mess.

Their conclusion: “Luck occurs at the intersection of random chance, talent and hard work.”