The Free Energy Principle

How minds minimize surprise to persist

GENERATIVE MODEL

Internal world-model

Belief: ~50

PREDICTION

Expected sensory input

~50

SENSORY INPUT

Actual observation

~50

PREDICTION ERROR

Mismatch signal

~0

MODEL UPDATE

Perception: change beliefs to fit world

+0.0

ACTION

Action: change world to fit beliefs

+0.0

WORLD (HIDDEN STATE)

50

TWO WAYS TO MINIMIZE SURPRISE: update the model (perception: change beliefs to fit the world) or change the world (action: change the world to fit beliefs).

Free Energy (rises with prediction error) 0
0 (fully predicted) 100 (maximum surprise)

The model predicts sensory input and minimizes prediction error...

3

Free Energy Over Time (learning history)

generative modelpredictionsensory inputprediction errormodel updateaction