What is Integrated Information Theory?

Integrated Information Theory (IIT) is a prevailing theory aimed at explaining the nature and structure of consciousness through mathematical and informational frameworks. Developed by Giulio Tononi, IIT posits that any system with a high degree of integrated and differentiated information possesses the property of consciousness. This measure of consciousness is quantified using a mathematical value called "phi" (Φ), representing the degree of integrated information in a system. According to IIT, a higher phi implies a higher degree of consciousness 1 2.

David Chalmers acknowledges that IIT provides a precise mathematical framework, establishing specific predictions about consciousness. However, he critiques its application, suggesting that even simple systems can exhibit high phi, which might lead to implausible conclusions about their consciousness levels. He notes that the theory could miss key aspects of consciousness, like self-representation and world representation, requiring further refinement for broader acceptance 2 3.

Heather Berlin explains that IIT treats consciousness as a fundamental property of the universe, akin to gravity. The theory suggests that even basic systems, such as light switches, might have a tiny degree of consciousness due to their informational states, leading to philosophical implications like panpsychism 1.

Overall, IIT attempts to rigorously quantify consciousness through integrated information, but faces challenges and debates regarding its practical and philosophical implications.