But while the folklore surrounding lucky coins is all about attracting good things, the vast majority of superstitions out there are different. They are beliefs designed to repel danger and suffering, either by watching for ominous signs or by actively tripping up the evil forces that might deliver the worst that life has to offer. Many of these superstitions have been with us for a very long time, and while they can be a bit divisive, splitting communities into those who believe and those who don’t, it’s undeniable that they hold a certain kind of power of us–a power that has driven some people to the very edge of madness. And if history is any indication, there’s a good reason why.

Knock on wood; never walk beneath a ladder; a broken mirror means seven years of bad luck; toss spilt salt over your left shoulder. Aaron Mahnke delves into the origins of these common superstitions in the latest episode of his Lore podcast. Somewhat surprisingly, many of these fears that still have lingering effect on people’s behavior today actually link back to ancient times. Mahnke lets the roots of such superstitions show, explaining in delightfully enlightening manner the various theories of their initial development. Along the way, he also ties cultural artifacts into the narrative, as when he invokes Da Vinci’s The Last Supper.

The bulk of the episode, though, is devoted to the fear of numbers, and it is interesting to learn of the negative connotation that Asian cultures give to the numbers 4 and 9. Add those two digits, and you arrive at the most number of all: Mahnke unpacks the origins of the superstitious dread of the number 13 and the date Friday the 13th (with nary a mention of slasher movies). Turning to the world of classical music, he details how composer Arnold Schoenberg’s triskaidekaphobia became something of a self-fulfilling prophecy, and how Gustav Mahler’s attempt to circumvent the “curse of the ninth” (the belief that a ninth symphony will be the last for a composer, who will die before completing the 10th) apparently backfired. In summation, “Adding It Up” equals another terrific episode of the podcast.

Note: not coincidentally, Episode 154 (with its discussion of the number 13) ties into a new project set to launch on the 19th: Aaron Mahnke’s 13 Days of Halloween. So there’s even more to look forward to this October than weekly Lore installments.