From the book, Stumbling upon Happiness by Daniel Gilbert
To see is to experience the world as it is, to remember is to experience the world as it was,
but to imagine – ah, to imagine is to experience the world as it isn’t and has never been, but as it might be.
The greatest achievement of the human brain is its ability to imagine objects and episodes that do not exist in the realm of the real, and
it is this ability that allow us to think about the future.
As one philosopher noted, the human brain is an “anticipation machine,” and “making future” is the most important thing it does.
Whatever you are thinking, your thoughts are surely about something other than the word with which this sentence will end.
But even as you hear these very words echoing in your very head, and think whatever thoughts they inspire, your brain is using the word it is reading right now
and the words it read just before to make a reasonable guess about the identity of the word it will read next, which is what allows you to read so fluently.
Any brain that has been raised on a steady diet of film noir and cheap detective novels fully expects the word night to follow the phrase, “It was a dark and stormy,”
and thus when it does encounter the word night, it is especially well prepared to digest it.
As long as your brain’s guess about the next word turns out to be right, turning black squiggles into ideas, scenes, characters, and concepts,
blissfully unaware that your nexting brain is predicting the future of the sentence at a fantastic rate.
It is only when the brain predicts badly, that you suddenly feel avocado.
That is, surprised. See?
Now, consider the meaning of that brief moment of surprise. Surprise is an emotion we feel when we encounter the unexpected.
The surprise you felt at the end of the last paragraph reveals that as you were reading the phrase it is only when your brain predicts badly that you suddenly feel…,
your brain was simultaneously making a reasonable prediction about what would happen next. It predicted that sometime in the next few milliseconds
your eyes would come across a set of black squiggles that encoded an English word that described a feeling, such as sad or nauseous or even surprised.
Instead, it encountered a fruit, which woke you from your dogmatic slumbers and revealed the nature of your expectations to anyone who was watching.
Surprise tells us that we were expecting something other than what we got, even when we didn’t know we were expecting at all.