You are sitting in a comfortable chair by the fire, on a cold winter’s night. Perhaps you have a mug of tea in hand, perhaps something stronger. You open a magazine to an article you’ve been meaning to read. The title suggested a story about a promising — but also potentially dangerous — new technology on the cusp of becoming mainstream, and after reading only a few sentences, you find yourself pulled into the story. A revolution is coming in machine intelligence, the author argues, and we need, as a society, to get better at anticipating its consequences. But then the strangest thing happens: You notice that the writer has, seemingly deliberately, omitted the very last word of the first .
The missing word jumps into your consciousness almost unbidden: ‘‘the very last word of the first paragraph.’’ There’s no sense of an internal search query in your mind; the word ‘‘paragraph’’ just pops out. It might seem like second nature, this filling-in-the-blank exercise, but doing it makes you think of the embedded layers of knowledge behind the thought. You need a command of the spelling and syntactic patterns of English; you need to understand not just the dictionary definitions of words but also the ways they relate to one another; you have to be familiar enough with the high standards of magazine publishing to assume that the missing word is not just a typo, and that editors are generally loath to omit key words in published pieces unless the author is trying to be clever — perhaps trying to use the missing word to make a point about your cleverness, how swiftly a human speaker of English can conjure just the right word.
Before you can pursue that idea further, you’re back into the article, where you find the author has taken you to a building complex in suburban Iowa. Inside one of the buildings lies a wonder of modern technology: 285,000 CPU cores yoked together into one giant supercomputer, powered by solar arrays and cooled by industrial fans. The machines never sleep: Every second of every day, they churn through innumerable calculations, using state-of-the-art techniques in machine intelligence that go by names like ‘‘stochastic gradient descent’’ and ‘‘convolutional neural networks.’’ The whole system is believed to be one of the most powerful supercomputers on the planet.