What is the bootstrap paradox?

Hey, this is a super interesting question! The Bootstrap Paradox sounds really mystical, but it's essentially an upgraded, time-traveling version of the classic 'chicken and egg' dilemma.

I'll try my best to explain it in simple terms.

One-Sentence Explanation

It's when an object or a piece of information forms a closed loop in time, and you can't find its "origin" or "starting point." It's like a story without an author that simply created itself.

Here's a classic example to help you understand

Imagine this scenario:

You're a huge fan of Beethoven's music. One day, you get your hands on a time machine and decide to travel back to the 18th century to meet your idol.
Once in the past, you excitedly ask around, only to discover... there's no musician named "Beethoven" in this era! You're completely bewildered.
To prevent those magnificent works (like the 'Symphony No. 5' or 'Moonlight Sonata') from vanishing forever, you rely on your incredible memory, transcribe all of Beethoven's scores from memory, and then publish them under the name "Beethoven."
Thus, this music becomes famous and, centuries later, a music fan named "you" hears these great works, falls deeply in love with them, and decides to get into a time machine to go back and meet this great composer...

See, a perfect closed loop is formed.

So, the question is: who actually composed Beethoven's music?

Not you, because you "heard" it from the future.
And not Beethoven, because he didn't exist until you created him.

The music simply appeared out of thin air within this time loop, with no origin and no original creator. This is the Bootstrap Paradox. The name "Bootstrap" comes from the English idiom "pull oneself up by one's own bootstraps," meaning to "succeed by one's own efforts," but here it implies the contradictory sense of "creating something out of nothing, self-creation."

The Core Contradiction of the Bootstrap Paradox

What's most mind-boggling about this paradox is how it challenges our most fundamental common sense:

No Origin: Everything should have a source. A book needs an author, a cup needs a craftsman. But in the Bootstrap Paradox, this origin disappears; it is its own source.
Causal Loop: Normal cause-and-effect relationships are linear (A leads to B). But in the Bootstrap Paradox, the causal relationship becomes a loop (A leads to B, and B in turn leads to A). You went back in time because you heard the music, and you created the music by going back in time.
Violation of Information Conservation?: From a physics and philosophical perspective, information and matter cannot be created out of nothing. But in this paradox, a great symphony simply "comes into being" without any intelligent input in its creation process, merely being "copied" in a loop.

How is it different from the "Grandfather Paradox"?

You might have heard of another famous time travel paradox – the Grandfather Paradox (If you go back in time and kill your grandfather, would you still exist?).

These two are easily confused, but the distinction is crucial:

Grandfather Paradox: Its core is about changing the past. Your actions would create a completely different, contradictory future from the history you know. It discusses "whether history can be changed."
Bootstrap Paradox: Its core is about being unable to change the past, and you yourself being part of that past. Your actions not only don't change history, but actually facilitate the history you know. It discusses "history as a fated closed loop."

In other words: The Grandfather Paradox is about "you going back and messing up the past," while the Bootstrap Paradox is about "you going back and, precisely, becoming part of the past."

Examples in Film and TV

Many sci-fi works love to play with this trope:

The Terminator: Skynet sends a Terminator back in time to kill Sarah Connor, while the future John Connor sends Kyle Reese back to protect her. As a result, Kyle Reese and Sarah fall in love and conceive John Connor. Therefore, John Connor's very existence is a Bootstrap Paradox; without Kyle Reese's time travel, he wouldn't exist.
Harry Potter and the Prisoner of Azkaban: Harry is under attack by Dementors by the lake, and at a critical moment, he sees a mysterious figure cast a powerful Patronus Charm to save him. He believes it's his deceased father. Later, he uses a Time-Turner to go back to that moment and discovers that the mysterious figure who cast the Patronus Charm was himself. The reason he was able to cast the spell successfully was precisely because he had "already seen" himself succeed.

To summarize

The Bootstrap Paradox is a logical conundrum about "unoriginated objects" or "unoriginated information." It depicts a deterministic view of time, where all events are preordained, and a time traveler's every action is merely one link in this grand script, from which they cannot deviate, and which may even be the reason the script exists in the first place.

It challenges our fundamental understanding of causality, time, and creation. What you perceive as the "cause" might, in fact, be its own "effect." Isn't that both cool and mind-bending?