The RL Spiral, Part 4: When RL Learned to See

For decades, every RL system needed a human to tell it what to look at. Then one opened its own eyes. The headlines went to the neural network. The less celebrated ingredient came from a sleeping rat.

This is the fourth article in The RL Spiral, an eight-part series on reinforcement learning. The previous article, The Curse Bellman Couldn’t Break, explained why RL needs so much experience. This one is about the moment that changed.