You started with a question that felt simple: can machines think?

It isn't. The closer you get, the more you realize the question itself is slippery. "Thinking" means different things depending on how you look at it, and nobody has agreed on a definition that holds up.

No one has an answer. But that's not a dead end. It means you're looking at the question clearly, which is a better place to start than a false one.

The people who built the first AI systems didn't see it that way. They thought the question was basically solved. What happened next is the story of what it cost them to find out it wasn't.