The Extended Mind 1. The Extended Body: It’s not implausible to think that, in some cases, parts of the external world become a part of our bodies. For instance, it is reasonable to think that a prosthetic limb is an extension of—i.e., a PART of—that person’s body. Perhaps too, things like pacemakers, hearing aids, canes, etc. are all a PART OF the bodies of those who have them. There may be other cases too: For instance, a great musician will often claim that their instrument is a “part” of them; they “become one” with their instrument. But, what if the mind is like that? That is, what if the mind extends beyond the brain? 2. The Extended Mind: We manipulate the world in order to aid and augment some cognitive processes all the time (call this an epistemic action). We use scrap paper (or our fingers!) to figure out tough math problems, we write down important things so that we can remember them, and so on. Now, imagine that you are asked to determine how various shapes ought to be rotated and arranged in order to form a perfect square: You solve this puzzle in three different scenarios: (a) You perform the rotations in your head in order to figure it out. (b) You figure it out using a neurally-implanted computer chip which you can operate with your brain to visually rotate each shape inside your head. (c) You figure it out using an external computer, pressing keys to manually rotate each shape on a screen. You then solve the puzzle (pictured to the right). Clearly, solving the puzzle the old-fashioned way, “in your head”, is a cognitive process of your mind. Now ask: Are the processes that occur in (b) and (c) also cognitive processes of the mind? If not, why not? In scenario (a), you consciously manipulate a part of the world—namely, your brain—in order to solve the puzzle. Are the other two scenarios any different? 1 Privilege brain-matter? If you think about it, when you use a computer that is inside your head, (b), you are ALSO consciously manipulating some part of the world in order to solve the puzzle—only, the stuff inside of your head that you are manipulating is not organic brain matter, but rather a computer chip. Is the BRAIN, or CARBON somehow privileged over, say, SILICON? There doesn’t seem to be any good reason for such discrimination. [Or is there? Do you agree?] Privilege the inside of the skull? Furthermore, the only difference between (b) and (c) is the LOCATION of that computer—namely, OUTSIDE of your skull, rather than inside. So, is the location INSIDE of the skull somehow privileged over those locations that are outside of it? This doesn’t seem like a justifiable discrimination either. [Do you agree?] But, once we reject the claim that there is are no good reasons to insist that (i) the material of the mind is restricted to organic brain matter, or that (ii) the location of the mind is restricted only to those locations inside the skull, an interesting thesis arises: The Extended Mind Thesis. This thesis is the first premise of the following argument: 1. The Extended Mind Thesis: If a part of the world functions as a process which, were it done in the head, we would have no hesitation in recognizing it as part of our cognitive process, then that part of the world is part of our cognitive process. 2. Your iphone functions in such a way. 3. Therefore, your iphone is a part of your cognitive process (and thus, your mind). 3. Objections: Here are some worries: 1. In order for something to be a cognitive process, it must be conscious (unlike iphone). Reply: That’s simply not true. Many cognitive processes occur unconsciously. 2. The mind is portable. It goes with you wherever you go. External objects do not. Reply: Even if this were a requirement for something to be a part of your mind, we could still include things like your iphone as a part of your mind, since it too is portable, and reliably goes with you wherever you go. 3. Admitting that, e.g., an iphone is a part of my COGNITIVE PROCESSES does not entail that it is therefore a part of my MIND. Reply: Consider the following two stories: 2 Inga: Inga just heard that the new Star Wars movie came out today. She forms the desire to go see it. She thinks for a moment and recalls that the movie theater is in New Town. She goes and sees the movie. Otto: Otto suffers from Alzheimer’s disease. He has trouble forming new memories. He carries around a notebook where he keeps important information that he wants to remember. Otto has just heard that the new Star Wars movie came out today. He forms the desire to go see it. He consults his notebook and it says that the movie theater is in New Town. So he goes there and sees the movie. Now, clearly Inga believes that the proposition <The movie theater is in New Town> is true. Furthermore, she believes this BEFORE she consults her memory. Surely, we do not want to say that people only believe things that they are CURRENTLY thinking of. (Call these occurrent beliefs.) Admittedly, her belief is not an OCCURRENT belief. We might instead call it a dispositional belief—i.e., she is DISPOSED to report that she believes this proposition when asked. But, ask yourself: Do you have beliefs that you are not currently thinking of? E.g., don’t you believe that you live in Williamsburg, that you are a human being, and so on, even when you are not consciously thinking about these beliefs? So, Inga’s beliefs are stored in her brain—and beliefs are a part of the mind. But, the two cases are completely analogous except for the fact that Otto must consult a notebook instead of his brain. So, it seems that Otto ALSO believes that <The movie theater is in New Town> even BEFORE he consults his notebook. So, Otto’s beliefs are stored in his notebook—and beliefs are a part of the mind. Therefore, a part of Otto’s mind is in his notebook. The alternative is to say that, at best, Otto believes that the movie theater is wherever his notebook SAYS it is. But, then, in Inga’s case, we would have to say that, at best, she merely believes that the museum is wherever her memory has recorded that it is. But, this doesn’t seem to be what she believes. Or at least, that is not ALL she believes. Imagine if I asked you, “Do you believe that you live in Williamsburg?” and you replied, “I’m not sure. I only believe that I live wherever my memory tells me I believe. Hold on.” [consulting memory] “Yes, now I believe that I live in Williamsburg.” That is absurd. Chalmers says this is “one step too many”. For simplicity, we should just cut out this middle-man. He writes: The moral is that when it comes to belief, there is nothing sacred about skull and skin. What makes some information count as a belief is the role it plays, and there is no reason why the relevant role can be played only from inside the body. 3 Rebuttal: We might insist that there are relevant disanalogies between Inga and Otto’s case, which entail that Inga has the non-occurent belief but Otto does not: Inga’s belief is in her head, but Otto’s is outside of his head. Reply: We cannot simply STIPULATE this. That is “begging the question”—i.e., assuming to be true the very claim that is being debated. Inga’s belief “stays put”. It is reliable, and doesn’t “come and go” as Otto’s notebook might. It would seem odd to say that Otto only has certain beliefs when he is carrying his notebook with him, but that he “forgets” things when he accidentally leaves it at home. Reply: But, Inga’s beliefs don’t really “stay put” either. They “come and go” too (e.g., when she is sleeping, or intoxicated). As long as they are reliably retrievable under certain conditions (e.g., when she is awake, sober, parts of her brain are not removed by an evil neuroscientist, etc.), then we can still attribute non-occurrent beliefs to her. Similarly, as long as Otto’s beliefs are reliably retrievable under certain conditions (e.g., when he is awake, sober, his notebook is with him, etc.), then we can say the same of Otto. And his beliefs ARE reliably retrievable under these conditions! Otto’s belief is gained by PERCEPTION (i.e., LOOKING AT his notebook). Meanwhile, Inga’s belief is gained by INTROSPECTION (i.e., looking INWARD, mentally). Reply: But, the phenomenological FEEL of retrieving a belief, memory, etc., does not seem important. We might imagine a being who has to use his EYES to recall memories, form occurrent beliefs, etc. (Chalmers mentions The Terminator as being portrayed in this way.) Conclusion: Unless you want to deny the existence of non-occurrent beliefs, then we must accept that Otto’s mind extends into his notebook. In short, the mind “ain’t all inside of the head”! 4. Some Implications: The Extended Mind Thesis is not just an interesting philosophical thesis. If true, it may have some surprising implications for the way we view the world: Exams test your mind’s ability to figure out problems, etc.