Era 01 / 15 · Cybernetics 1943–1948

Cybernetics

Machines could steer themselves — control as feedback, not command.

01 · concrete  the steersman

A boat finds the light

Wind pushes it astray; it senses the error and corrects. The wavy path is the feedback.

A boat steering toward a lighthouse A boat sails toward a teal lighthouse on the right. Wind pushes it off course, so it follows a wavy correcting path rather than the straight dashed ideal line — a feedback loop made physical. Coral marks error, teal marks the goal. GOAL ideal straight course WIND · the disturbance ERROR START
goal / rudder error & correcting path wind & ideal line motion reduced — boat frozen mid-correction

02 · abstract  the loop, stripped bare

The same loop, stripped bare

Strip the sea away and the correction is this cycle: goal → error → correct → move → repeat.

The feedback loop, abstracted The boat scene redrawn as an abstract closed loop. A token circulates clockwise through five nodes — goal, error, correct, move, new state — and back to goal. Teal nodes are goal-aligned, coral nodes are error, sand nodes are mechanism. The same mechanism as the boat. GOAL the light ERROR off course CORRECT rudder MOVE NEW STATE sense · correct · repeat
goal-aligned error / the deviation in motion mechanism

03 · interactive  the homeostat

Now disturb it yourself

A whole field running the loop at once = homeostasis. Push it into error; watch it steer back to rest.

DISTANCE FROM GOAL at rest
Drag the field — watch it settle back
Disturbedfar from goal · coral
Re-equilibratedat goal-state · chartreuse
disturbance / far from goal equilibrium / at goal-state motion reduced — before / after shown statically
kybernetes → steersman → governor → cybernetics
Founding texts & the people
1948 · Wiener
Cybernetics
Norbert Wiener names the field: control and communication in the animal and the machine. One loop for both.
1943 · McCulloch–Pitts
Threshold neuron
A neuron as a logic gate: sum the inputs, fire past a setpoint. The brain as a steering circuit.
1948 · Shannon
Signal & noise
Information as a measurable signal through a noisy channel. Feedback needs a message to act on.