The Perceptron
Back to Mr Rosenblatt. He was a psychologist, not a mathematician or an engineer. He came at the problem from the direction of the brain, not from logic or rules.
The machine he built reflected that. The Perceptron was not a program. It was a machine.
A camera fed an image in. Each patch of the image became a number.
Those numbers flowed through weights. In the Perceptron, the weights were physical dials that motors could turn.
The machine added the weighted signals and made a guess. If the guess was wrong, the motors nudged the dials.
That was the perceptron idea made physical: input numbers, adjustable weights, one output, correction after mistakes.