Such games are said to have “dense” rewards, which makes them relatively easy to learn.

As we’ve seen, one of the small but powerful techniques that made AlexNet so successful in 2012 was an idea known as “dropout”: certain parts of the neural network would be turned off—certain neurons simply would be “unplugged”—at random during each step of training.

The third advantage of imitation is that it allows the student (be it human or machine) to learn to do things that are hard to describe.

Infants’ preference for looking at new things is so strong, in fact, that psychologists began to realize that they could use it as a test of infants’ visual discrimination, and even their memory.

also seems that babies are keenly aware of when they’re being imitated.

“You start to pin it to incentive, motivation, as a response to a stimulus that makes you move. . . .

behaving predictably presumes that the observer knows what your goal is; behaving legibly presumes they do not.

At the other side of the spectrum from boredom is addiction—not a disengagement but its dark reverse, a pathological degree of repetition or perseverance.

cooperation works best when it is framed as an interaction, not as two separate and distinct “learn, then act” phases.