ELI5: Explain Like I'm 5

Jacobi identity

The Jacobi identity is like a rule in math that has to do with different operations that use three different things. Imagine you have three toys, let's say a ball, a teddy bear, and a toy car.

Now, let's say you want to play with these toys in different ways. You can throw the ball to the teddy bear, and the teddy bear can pass it on to the toy car. This is one kind of game you can play, and we call it "operation" in math.

Another operation you can do is to swap the toys around. For example, you could put the teddy bear in the place where the toy car was, and move the toy car where the ball was.

If you do these kinds of operations a lot, you might wonder if there are any rules that always apply, no matter what toys you're playing with or what kinds of games you're playing.

The Jacobi identity is one of those rules that always applies, no matter what toys or games you're playing. It says that if you do an operation in two different ways, and then do another operation after that, it doesn't matter which order you do the operations in.

For example, let's say you throw the ball to the teddy bear, then swap the teddy bear and the toy car, and then pass the ball to the teddy bear again. You could also do these operations in a different order: first swap the teddy bear and the toy car, then throw the ball to the teddy bear, and finally swap the teddy bear and the toy car again.

The Jacobi identity says that no matter which order you do these operations in, you should get the same result. It might sound a bit complicated, but it's a really important rule in math that helps us understand how different operations work together.
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