Some recent authors suggest that the extended view fails because it does not follow from functionalism. For although functionalism can tell us whether a system is cognitive, it does not show whether such a newly identified cognitive system can be attributed to the very same subject. I argue that Clark and Chalmers can dodge this attack by claiming that the Parity Principle is essentially an analogy. In their crucial thought experiment, it can be argued that Otto’s notebook is similar to (...) Inga’s biological memory in that they are functionally equivalent, and it seems that the only relevant difference between them is concerned with their being located inside/outside the skull/skin. Provided that Inga’s biological memory is part of Inga’s cognition, analogously, Otto’s notebook should also be regarded as part of Otto’s cognition. However, I argue that this alleged analogy does not hold because the location is not the only difference that matters. Otto’s notebook and Inga’s biological memory are taken as part of a whole for different reasons, and because of this, they actually belong to different kinds of wholes. Otto’s notebook is part of a whole because such a whole functions as a cognitive system, but Inga’s biological memory is part of a whole because it is within a “proper whole” whose boundary is determined by reproduction. As a result, the analogy does not really work. (shrink)