Last Monday , the Phillies’ Brad Miller bought a bamboo plant in Chinatown and placed it in his locker. His team was mired in a seven-game losing streak, and Miller thought bamboo would be good luck.

The Phillies won that night, so Miller returned to same store and bought an even bigger plant for the team’s clubhouse. Not only did the Phils win again, but Miller — a light-hitting utility player — hit a home run.

Then he got a third plant, which he put on manager Gabe Kapler’s desk. And the Phillies won for a third straight time.

So bamboo makes you succeed in baseball, right?

Of course not. That’s the essence of superstition, which my dictionary defines as “an unjustified belief in supernatural causation.” But it turns out that believing in superstition can actually help you, in certain circumstances.

In a 2010 study, university students were asked to putt a golf ball into a cup. Half the participants were told they received a “lucky ball,” and the other half were told that got the same ball everyone else used. Guess what? Although there were no differences between the two groups, the first group made 35 percent more putts.

Likewise, a 2007 study of Israeli women during the second intifada in the early 2000s found that nonreligious women who recited psalms in response to the violence felt more comfortable shopping, traveling, and entering crowds. That’s because they believed that the psalms would protect them, which is no more rational or scientific than the idea of bamboo winning baseball games. We call one religion and the other superstition, but they’re both based on supernatural faith. And they can both help you thrive and succeed, whether they’re “true” or not.

Hall of Fame baseball player Wade Boggs took batting practice at precisely 5:17 p.m. and ran wind sprints at exactly 7:17 p.m. He ended his infield practice by stepping on third, second, and first base, in the same order. Boggs ate chicken before each game and scrawled the Jewish word for “life” in the dirt before every at-bat, even though he wasn’t Jewish.

He ended his career with over 3,000 hits and a .328 batting average. Whatever he was doing, it certainly worked for Wade Boggs. “I don’t like surprises,” Boggs said. “I face enough of the unexpected when I’m hitting."

That tells us a lot about superstition, which is most common in circumstances where we feel we have the least control. In his classic 1948 study Magic, Science, and Religion, observing fishermen on the Trobriand Islands, British anthropologist Bronislaw Malinowski found that they were more likely to invoke magic and superstition when they ventured into deep and unfamiliar waters.

In some respects, baseball players do that whenever they come to the plate. They don’t know what pitch they will see, whether they’ll make contact, where the ball will go, or whether it will be caught. And even elite players like Wade Boggs fail more than two out of three times.

That’s why superstition runs rampant through the sport. Pitcher Turk Wendell brushed his teeth between innings. Slugger Jason Giambi wore a golden thong whenever he was in a slump. And Moises Alou would often urinate on his hands — yes, you read that right — as a good-luck charm.

Athletes in other sports have their own superstitions, too. Former Buffalo Bills quarterback Jim Kelly forced himself to vomit before every game. Basketball superstar Michael Jordan wore shorts from the University of North Carolina — his alma mater — under his pro uniform.

And there’s nothing wrong with that, so long as superstitions actually help you. I’d be curious to know what Jim Kelly’s doctor had to say about his own pregame ritual. Kelly surely believed it would aid his performance, but he could have been wrong.

If your astrologer tells you you’re going to ace a job interview, you might be less likely to prepare for it. And if she warns you that the stars aren’t aligned, you might simply throw in the towel.

So it all depends on you, actually, not on your stars. It’s silly to imagine that a new plant by itself can influence a baseball game. Strange as it sounds, though, there might be some rational reasons to believe in irrational things. Break out the bamboo, then! And go Phillies.

Jonathan Zimmerman teaches education and history at the University of Pennsylvania. He is the author (with Emily Robertson) of “The Case for Contention: Teaching Controversial Issues in American Schools” (University of Chicago Press).