it is often best to view the coupling considerations as a means not of directly establishing co-constitution so much as establishing ownership. The right kind of dense coupling (e.g. complex reciprocal causal exchange) is surely part of the explanation of why, for example, the right and the left neural hemispheres count – when the coupling takes just the right form – as two components of a larger processing system rather than as two isolated processors.Here, Clark highlights an important idea. Coupling considerations are often thought to establish ownership.
Coupling, however, does not tell you the character of what you own. Mere ownership of a thing does not tell you whether that thing is a mere tool or a cognitive processing unit. The fact that Otto is coupled to his notebook might tell you that it is his notebook and part of his cognitive system, but it doesn't tell you whether cognitive processing is taking place in that part of the system.
To switch examples, causal coupling between the CPU and the monitor may tell you that the monitor is part of the computing system, but it doesn't tell you whether the monitor computes. For that, one would need something like a "mark of the computational".
Even construed as ownership conditions, coupling is not entirely unproblematic. On the one hand, Clark does not want the coupling conditions to be too lax, since one will then "own everything". This would be a kind of "ownership bloat" problem on par with the more familiar "cognitive bloat" problem. On the other, Clark does not want the coupling conditions to be too stringent, since one will then not "own" things that one apparently does "own". In section 7.3.1 of The Bounds of Cognition, A&A in effect indicate how Clark's conditions imply a lack of ownership of what appears to be one's cognitive apparatus. For example, Clark's conditions of "trust and glue" seem to imply that a person with blindsight does not own the apparatus that enables him to detect objects in his "blind" field.