The quest for a unifying theory is not a new one

It is a concept that has eluded some othe most towering minds in science, but where philosophy and physics have failed, could neuroscience possibly succeed?

The 'Free Energy Principle' posits that all life, at every scale of organization—from single cells to the human brain, with its billions of neurons—is driven by the same universal imperative, which can be reduced to a mathematical function and that to be alive, is to act in ways that reduce the gulf between your expectations and your sensory inputs.

This seemingly straightforward but profoundly complex idea could have enormous implications for areas such as artificial intelligence, computational psychiatry, and could shed light on how we understand how the brain works.

Professor Karl Friston - Scientific Director of University College London’s Functional Imaging Laboratory joins Jonathan to discuss.