CONCEPT
Free-Floating Rationales
Dennett's term for the reasons for which a design exists without any reasoner having formulated them — the kind of rationality that evolved systems and trained networks alike embody without understanding.
Free-floating rationales are reasons that exist in the structure of a system without being represented anywhere as explicit thoughts. The peacock's tail has a rationale — sexual selection has shaped it toward a specific function — but no peacock and no designer formulated the rationale. Dennett coined the term to capture the peculiar fact that evolution produces rational designs without reasoners, and that much of biological intelligence is this kind of structured response to reasons that nothing in the system has ever thought. The concept maps directly onto large language models: the weights encode countless free-floating rationales for linguistic and inferential moves, none of them articulated by any agent, including the network itself.
In The You On AI Field Guide
The concept was developed most fully in Darwin's Dangerous Idea (1995) and elaborated in From Bacteria to Bach and Back (2017). It is the bridge between Dennett's account of Darwinian process and his account of mind: once you see that evolution produces