Compatibility of Six Theories of Consciousness

2026-10-07 Claude Opus 5.5 with prompts by jch.com/jch <> YON - Jan C. Hardenbergh

This table compares six leading theories of consciousness, pair by pair, and rates each pair as Compatible, Maybe, or Incompatible.

Key:

• GWT = Global Neuronal Workspace — Stanislas Dehaene
• HOT = Higher-Order Theory — David Rosenthal, Hakwan Lau
• AST = Attention Schema Theory — Michael Graziano
• PP = Predictive Processing — Karl Friston, Andy Clark, Anil Seth
• IIT = Integrated Information Theory — Giulio Tononi
• DMM = Dual Mental Model — Joe LeDoux¹

“Compatible” means the two theories could both be true or could be combined. These ratings are judgment calls, not an established consensus.

The incompatibilities

1. GWT vs IIT: GWT says consciousness is a function: information becomes conscious when it is globally broadcast across the brain, which any suitable hardware could carry out. IIT says consciousness is intrinsic causal structure, measured as integrated information (Φ), which function can’t supply. On IIT, a digital computer running a perfect global workspace would be essentially unconscious. The two were tested against each other in the Cogitate adversarial collaboration, and the results challenged both.
2. HOT vs IIT: HOT treats consciousness as representation about representation: a mental state is conscious only when another state represents it, with the prefrontal cortex playing a key role. IIT rejects representation as the basis of consciousness and places it in the integrated causal structure of posterior cortex. Hakwan Lau, a leading HOT proponent, signed the 2023 letter calling IIT pseudoscience.
3. AST vs IIT: AST is functionalist and leans toward illusionism. Awareness is a simplified model the brain builds of its own attention, so a machine that builds such a model would have whatever humans have. IIT says awareness is intrinsic, can’t be reduced to a model, and is essentially absent in digital machines.
4. IIT vs DMM: DMM places consciousness at the top of four nested realms of existence (biological, neurobiological, cognitive, conscious). It needs cognition, working memory, prefrontal re-representation and, for full self-awareness, autonoetic (self-knowing) memory. IIT gives some degree of consciousness to any system with Φ above zero, including very simple ones that have no cognition at all. DMM treats consciousness as a late evolutionary add-on, while IIT treats it as widespread and graded.