A new time- and state-dependent measure of integrated information, phi, quantifies how much information is generated when a system enters a particular state through causal interactions among its elements, beyond what its parts generate independently. This captures two key properties of consciousness: a large repertoire of experiences that rule out others when one occurs, and the integration of that information into a whole that cannot be decomposed. Applied to discrete networks, phi varies with the state entered, being higher when active and inactive elements are balanced and lower when the network is inactive or hyperactive.
Integrated information theory proposes that consciousness corresponds to the amount of integrated information generated by a system of elements, and the quality of an experience is determined by the informational relationships within that system. This paper introduces qualia space (Q), where each possible state of a system is an axis, and submechanisms specify repertoires of states. Arrows between these repertoires define informational relationships that together form a shape—a quale—that uniquely characterizes a conscious experience. The quantity of consciousness is the height of this shape (phi). Entanglement measures how irreducible these relationships are. The framework implies that the same activity pattern can yield different qualia in different systems, and vice versa. Experience cannot be reduced to local mechanisms but requires the entire quale.