Ssmall event causes big effect. What is this called?

What is this situation called? When a small (seemingly insignificant) decision or happening ends up drastically changing someone’s life (or many lives).

Example 1: Joe forgot to take a second glance before stepping out into the street. A second later he was struck by a car and ends up permanently crippled. His job changes, his wife leaves him, and even his friends treat him differently. Years later he commits suicide. All of this would have been avoided if he had just taken a second glance.

Example 2: Bilbo happens upon a ring. The fate of Middle Earth is changed.

I think of this situation as contrary to our normal thought that the big decisions shape our life (where we go to school, who we marry, where we live).

Butterfly effect?

I asked my wife this question after I posted it. This was her reply. This may be the best answer.

My original thought before my question morphed into a more general tone was “is this considered some literary device or does it have some name within movie/show/book production.” It is obviously used very often within the arts.

Butterfly effect is also what came to my mind first. I think it’s called that because of something like a butterfly flapping its wings can start up the breeze to build a hurricane over time somewhere else.

There’s also the “straw that broke the camel’s back” type of thing when some little thing causes a catastrophe. If there’s one word for that, I don’t know it offhand.

The one word is Marriage! Ha ha ha…

This was my first thought. See also “ripple effect” or “For Want Of A Nail.”

The “straw that breaks the camel’s back” is the most recent of a series of problems that causes a catastrophe. As in, the camel is already carrying a bunch of weight and it’s the weight of that last, teeny tiny straw that breaks it back.

If I’m at work and a customer spits in my face, I get demoted and my wife calls me up to let me know that she’s been cheating on me and that she’s leaving me… I can take it. But then my boss asks me to work Saturday. That’s when I go postal.

I’ve also heard it called the hinge effect - where a large turn of events hinges on one crucial decision or action.

Actually, that is not what the Butterfly effect meant originally, from what I understand. Chaos researcher used it to describe that weather, as a chaotic phenomen, exists of thousands time thousands events interacting with each other, and thus, it’s impossible to predict what happens*. If you change one parameter, no matter how small,** for example** the flap of a butterfly in the South American rainforest, then the interactions between all the other events can influence the path (not the existence itself) of a hurricane in the US 5 days later.

Since it will be impossible to ever count all butterfly wingflaps, or have the computing power** to model all the interactions between the events., it’s impossible to correctly predict the weather.

What the OP is describing sounds a bit different. He’s more talking about things happening and their consequences. I think that’s normal chaotic complexitiy of life, and the “common wisdom” that great changes in life are caused by big decisions are simply wrong and lacking in experience and data.

Or the domino effect.

  • Today, we have generally a 70% accuracy for 3 day forecasts. Beyond that, everything is unpredictable, beyond “shit happens”.

** One of the applications that demanded great computer processing power and supercomputers was not only artillery, but meterolgy. Predicting the weather accuratly has huge impacts on agriculture, shipping, etc.

As Freudian said, butterfly effect is probably the best answer. The terms comes from chaos theory, where a small change in initial conditions can lead to drastically different results.

Is the term butterfly effect perhaps also due to Ray Bradbury’s story, A Sound of Thunder?

The example of Joe not taking a second glance sounds like the snowball effect.

Marriage is not a word. It’s a sentence.

As a previous poster mentioned, it is indeed related to the Ray Bradbury story, “The Sound of Thunder.” Explorers go back in time and create catastrophic changes with tiny alterations. The story is great, by the way, certainly worth a read, and sets the “Rules” for any other story about time travel written subsequently.

It may be related to the Bradbury story, but was coined as an “effect” by Ed Lorenz. The Wiki article backs this up FWIW.

ETA: I know at least one person who thought the “butterfly” referred to the picture one gets when you look at the graph of the Lorenz attractor. It actually does sorta look like a butterfly, but has nothing to do with the origin of the term “butterfly effect”.

Nope. Lorenz specifically suggested the idea of a butterfly flapping its wings creating a hurricane to describe the difference in outcomes that such subtle changes early on in a process can wreak. Now it’s true that there are uncounted butterflies flapping their wings (and babies sneezing, and people flipping coins, and a million other things stirring small breezes), all of which interact in unpredictable ways. But the initial conception of the term was to show that undetectably small changes in initial conditions can lead to massively different outcomes.

Which leads us to another way to describe this phenomenon, as is used in scientific circles – “sensitivity to initial conditions.” Not as catchy as the Butterfly Effect, but it means the same thing.


The article says “The idea that one butterfly could eventually have a far-reaching ripple effect on subsequent historic events seems first to have appeared in a 1952 short story by Ray Bradbury about time travel (see Literature and print here) although Lorenz made the term popular.” Lorenz may have helped popularize the term but he appears to have gotten the specific idea of a butterfly originally from Bradbury (in some of his early papers Lorenz used a seagull).

I came to say domino or snowball effects but they were already taken. So +1 or whatever is fashionable at the moment.