Active Externalism

Case #1: Otto and Inga (from Clark and Chalmers)

  • Inga is the normal subject.
  • Otto suffers from Alzheimer's disease.

@Otto carries a notebook around with him everywhere he goes. When he learns new information, he writes it down. When he needs some old information, he looks it up. For Otto, his notebook plays the role usually played by a biological memory. Today, Otto hears about the exhibition at the Museum of Modern Art, and decides to go see it. He consults the notebook, which says that the museum is on 53rd Street, so he walks to 53rd Street and goes into the museum.@

  • C&C's parity principle (PP):

@If, as we confront some task, a part of the world functions as a process which, were it done in the head, we would have no hesitation in recognizing as part of the cognitive process, then that part of the world is (so we claim) part of the cognitive process. Cognitive processes ain't (all) in the head!@

Objection #1 - Real cognition requires non-derived content.

  1. Adams and Aizawa (2001) argues that a cognitive process must involve "non-derived content". The contents of the notebook derive from social linguistic conventions and so the notebook is not part of the cognitive process.
    • What if the notebook (+ OCR and camera) is integrated into the brain?
    • The relevant distinction is not between derived and non-derived content, but something else.
  2. Why not say that the physical boundaries of Otto is now extended to include the notebook?

Objection #2 - A less radical explanation is more plausible

@all Otto actually believes (in advance) is that the address is in the notebook. That's the belief (step 1) that leads to the looking (step 2) that then leads to the (new) belief about the actual street address.@

Clark: Why not say the same thing about Inga?

@Intuitively, the reason seems to be that in the case of Inga, the 2-step model adds spurious complexity: "Inga wanted to go to MOMA. She believed that her memory held the address. Her memory yielded 53rd St. ...". What's more, it seems likely that in the normal course of events Inga relies on no beliefs about her memory as such. She just uses it, transparently as it were. But ditto (we may suppose) for Otto: Otto is so used to using the book that he accesses it automatically when bio-memory fails. It is transparent equipment for him just as biological memory is for Inga. And in each case, it adds needless and psychologically unreal complexity to introduce additional beliefs about the book or biological memory into the explanatory equations.@

Objection #3 - C&C draw the wrong conclusion.

  • Uncontroversial - In principle, mental processes can occur outside the brain.
  • Controversial - In principle, mental processes can occur outside the subject.
  1. Regarding PP: How to determine whether two processes are the same or not? In terms of input-output equivalence, or sameness of algorithm?
  2. Is this a verbal issue? Is there anything theoretical important that depends on how the issue is to be resolved? C&C:

@By embracing an active externalism, we allow a more natural explanation of all sorts of actions. One can explain my choice of words in Scrabble, for example, as the outcome of an extended cognitive process involving the rearrangement of tiles on my tray. Of course, one could always try to explain my action in terms of internal processes and a long series of "inputs" and "actions", but this explanation would be needlessly complex.@

Case #2: Collective consciousness in The Matrix

Matthew Nagle, a quadriplegic fitted with the implant BrainGate

  • Imagine having neural implants that allow our brains to tap into Google's database to access information directly. The database would then become part of the whole cognitive process.
  • Should the database be regarded as being an internal or external part of the agent? Is there a correct answer?


  • Discuss the questions raised in the notes above.