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Many people believe that when Mercury is in retrograde, we become vulnerable to communication breakdowns, relationship turmoil, and misunderstandings with friends and loved ones, as if there is cosmic static or interference that gets in the way of our normal communication patterns and so major decisions, like signing a contract or starting a new venture, should be delayed during this period.

It's not true.

Further, some adherents to beliefs about Mercury in retrograde speculate that, depending on the cycle, certain Zodiac signs are more likely to suffer, such as the "mutable" signs of Virgo, Sagittarius, Pisces, and most acutely, Gemini.

That's also not true.

What should we make of the persistent popularity of such astrological claims? Is there anything we can take from them? Here are three ways to consider the phenomenon from a scientific standpoint.

Start with the astrophysics

We are currently in a “Mercury retrograde” cycle, which began on August 23 and will continue until September 14. Astronomically speaking, this cycle occurs about every four months and lasts approximately three weeks. It is an optical illusion of sorts, in which Mercury, from Earth’s vantage point, appears to change direction and move backward across the sky, before returning to its usual path.

Its apparent path shift, however, is completely explainable and occurs whenever you have two planets orbiting the sun at different distances and speeds. (Here is a useful video to help visualize the illusion.)

Does any research support the idea that Mercury in retrograde affects mental health?

The short answer: No. But there’s a little more to the story.

For one, it’s not wrong to suggest that Earth’s position in the solar system can impact our mental health. Look no further than seasonal affective disorder, which is estimated to impact as much as 5 percent of the adult population.

It’s also not wrong to say that what you believe in, even if it’s untrue or not based in reality, can profoundly impact your mental state. The power of placebos is one example—or consider psychological disorders such as “medical school syndrome,” in which a perfectly healthy medical school student starts to experience the symptoms of a particular disorder or disease they are learning about.

Our brains are powerful, sense-making machines—and they can be quite good at weaving what feels like a truthful narrative out of a series of speculative or misguided observations.

With that said, science has yet to discover any evidence to suggest that Mercury retrograde cycles have any affect on the human experience, beyond what people may believe, and artificially reify, about such cycles. Even looking at Zodiac signs and astrology more broadly, there is no scientific evidence to suggest that any of these models of personality are based on anything more than storytelling. For example, one study conducted on a sample of more than 170,000 Chinese adults found no association between a person’s astrological sign and their personality traits: Geminis were no more “temperamental” than others, and Virgos were no more “critical."

Is it harmful to believe in fallacies like astrology?

Not necessarily. In fact, believing in ideas that blur the lines between truth and fantasy may have some unique socio-psychological benefits. For example, how many times have you been able to strike up a conversation with a stranger or acquaintance around the topic of astrology and come out of it feeling like you know them better afterward? These enduring narratives can be powerful bonding agents—incredibly useful in a society that depends upon cooperation and interconnectedness.

In the case of Mercury retrograde, regardless of whether you believe in the premise—and even if you well understand that it's bunk—it is always a good idea to heed a reminder to work more closely on communication in our close relationships.

There is a point at which these pseudoscientific explanations can become problematic. In the case of Zodiac signs, the research cited above found that, in China, hiring managers may discriminate on the basis of astrological signs—and are especially prejudiced against Virgos. “Anecdotally, in China, there are personality stereotypes associated with the astrological signs,” say the researchers, led by Jackson Lu of the Massachusetts Institute of Technology. “In particular, some people intentionally avoid Virgos (those born between August 23 and September 22) as friends, romantic partners, or employees, purportedly because Virgos are stereotyped as having disagreeable personalities.”

It’s OK for hiring managers to be prejudiced against disagreeable personalities, but it’s not OK for them to be prejudiced against Virgos. Likewise, it’s OK for us to use Mercury retrograde cycles as a time to be gentle with ourselves and extra-attentive to our close relationships, but it’s not OK for us to use it as an excuse for relationship problems we are unwilling to address directly.