Prophecies are a favorite gimmick of authors. They are used as motivators, suspense builders, and are even necessary for some plots to happen. In fact, a lot of plots are reliant on the prophecies that predict them, even if it isn’t obvious from the beginning.
A more obvious example of this is the major prophecy in Harry Potter. Basically, the prophecy predicts the child who would defeat Voldemort, the big bad of the series. However, this wouldn’t have happened if Snape, one of Voldemort’s followers, hadn’t overheard the prophecy and told his master.
Voldemort responded by finding the two children who the prophecy could be about, and then picking one of the two to kill – Harry Potter. Lots of drama ensues, and eventually Voldemort finds the Potters’ house and sets on the path to kill Harry.
What actually ends up happening is Harry’s mom, Lily, sacrifices herself to save Harry. This protects him from Voldemort, so Voldemort’s spell rebounds and ends up almost killing him. Years later, he is reborn/revived/rebodied, and obsessively hunts Harry down.
This obsession leads to the series of events that make Harry the “owner” of Voldemort’s wand, which causes the spell to rebound again, except actually killing Voldemort. It also puts Harry strongly into the battle against horcruxes, which were keeping him alive.
If it wasn’t for the prophecy, there is a good chance Harry wouldn’t have been a part of Voldemort’s demise at all, though he no doubt would have fought against him. What makes him so special, so much more vital than the other students who fought Voldemort was the prophecy.
Example two is in the TV show Merlin. Throughout the series, the dragon Kilgarrah constantly warns Merlin against Mordred, saying that he will be Arthur’s downfall. In the last season, Merlin receives a prophecy saying the same thing, only more specific.
So Merlin, still burned from Morgana’s betrayal, treats the now Sir Mordred with suspicion and contempt, and even tries to have him die in multiple episodes. However, despite past conflicts, Sir Mordred is a loyal knight to King Arthur, and receives more responsibility and respect as the season progresses. If Merlin hadn’t known about his fate, he would be at least impressed in Mordred’s loyalty. But he had, and this turns into Mordred disliking Merlin as well.
Then, in the third-to-last episode, Mordred rediscovers a childhood friend, Kara. Kara, however, idolizes Morgana, Arthur’s enemy. So she tries to kill the king, and is arrested. Mordred does everything he can to free Kara. Merlin overreacts and has both Mordred and Kara caught. And it is this overreaction, more than anything, that turns Mordred and leads him to kill Arthur in the next episode.
The two Percy Jackson series provide examples 3 and 4. Both series have a main prophecy that directly influences the character’s actions.
Heroes of Olympus has the more obvious of the two. The prophecy talks about seven demigods who would defeat Gaia, the new big bad of the series. So Hera takes matters in her own hands, chooses the seven herself, and switches two of the main characters in an attempted diplomatic act.
If it wasn’t for the prophecy, it is highly doubtful that seven demigods would have been chosen. In the series, the lucky number is three – a fact that is highlighted a lot in the previous series. So three from one camp, three from the other would be the natural conclusion – that is if the camps ever met, since it was Hera’s plan that led them to collide.
The first series is less obvious, but its still there. The prophecy is given years before, and has long-lasting effects. The biggest is the ban on the big three gods (Zeus, Poseidon, and Hades) having children, but that is not the effect that matters here.
In the last book of the series, The Last Olympian, Percy, the main character, discovers that Hades puts a course on the oracle after losing one of his lovers thanks to the prophecy. Later, it is revealed that the antagonist Luke’s mother tried to be an oracle. Due to Hades curse, she goes mad instead. This leads to Luke’s story on why he hates the gods so much. This also leads to him meeting Thalia, who turns into a tree, which makes Luke hate the gods more. So Luke hates the gods because his mom is insane because Hades put a curse on the oracle because of the prophecy she spoke.
So in conclusion, a lot of prophecies are self-fulfilling. If there are any aspiring writers out there, this could be an interesting point in your book, justifying the prophecy’s existence.
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