Abstract
It is widely held that there is an asymmetry between our access to our minds and our access to others’ minds. Philosophers in the literature tend to focus on the asymmetry between our access to our mental states and our access to those mental states of others that are not shared by us. What if a mental state can have multiple subjects? Is there still an asymmetry between our access to our mental states and our access to those mental states of others that are also ours? In this paper, I discuss the implications of a case of shared consciousness—the case of the Hogan twins—for asymmetry. I start by clarifying the notion of asymmetry. Here I develop a characterization of asymmetry and argue that it is preferable to the standard approaches in the literature. I then present the twins’ case and argue that it does not threaten asymmetry. I close by drawing some lessons.
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Notes
Since there are no reports of shared unconscious mental states, in what follows I will mainly focus on shared consciousness.
An exception is Kriegel (2017). Kriegel is primarily concerned with the link between consciousness and dignity. Central to Kriegel’s account is the notion of “phenomenal inviolability,” according to which “every experience can be experienced by only one person” (p. 131). Although Kriegel mentions that the twins’ case is the only known exception to “phenomenal inviolability,” where each can access the other’s experiences in the same way that the other can, he says little to defend his view on the twins’ case. As I will argue, even if the twins’ case is an exception to “phenomenal inviolability,” there is still an asymmetry between each’s access to her experiences and her access to the other’s experiences.
In fact, even Ryle (2009) can accept ASYMMETRYe. On Ryle’s view, the difference between our access to our minds and our access to others’ minds is a difference in “the supplies of the requisite data” (p. 138). It is not just that we have more evidence about ourselves. We have certain sorts of evidence—such as memory and inner speech—that are unavailable to others. In the terminology to be introduced below, Ryle can be seen as an early proponent of the INTERNAL PROMPTING version of ASYMMETRYe.
I should say that although philosophers in the literature tend to focus on immediate justification and inferential justification, JS allows that asymmetry consists in a difference in other kinds of justification.
For a survey of how widespread IMMEDIACY is among philosophers, see Carruthers (2011, pp. 17–19).
On Lawlor’s view, Katherine’s self-ascription is the product of an inference about the cause of her internal promptings—Lawlor calls this route to self-knowledge “causal self-interpretation” (p. 49)—and it is justified in so far as it is the best explanation of her internal promptings.
Carruthers (2011) arguably endorses INTERNAL PROMPTING as far as attitudes are concerned, even though he does not use the term “internal prompting.”
Unlike Lawlor and Wikforss, Cassam has much to say about our access to our internal promptings. For discussion, see Cassam (2014, pp. 163–166).
Even Cassam, who is arguably the staunchest defender of INTERNAL PROMPTING, agrees that IMMEDIACY may be plausible when it comes to “simple feelings or sensations like nausea and pain” (2014, p. 164) and occurrent thoughts (2017).
These are different options. You can see that your mom is angry, or see her anger, only if she is angry, but you can see her as angry even if she is not angry. Assuming that seeing that p entails believing that p, you can see that your mom is angry only if you believe that she is angry, but you can see her anger without believing that she is angry.
To avoid this problem, proponents of INTERNAL PROMPTING might retreat to the following position:
INTERNAL PROMPTING*: You can have inferential justification to believe that you are in a mental state M from your internal promptings, but others cannot have inferential justification to believe that you are in M from their internal promptings.
Unlike INTERNAL PROMPTING, INTERNAL PROMPTING* characterizes asymmetry negatively, leaving open how others have justification to believe that you are in M.
Proponents of INTERNAL PROMPTING* need not deny that asymmetry holds in the anger case if you have immediate access to your mom’s anger. This is so because they are not committed to the view that you can only have inferential justification to believe that your mom is angry from your observation of her behavior. However, they will leave the asymmetry in the anger case unexplained. This is so because INTERNAL PROMPTING* foregrounds cases involving inferential justification and so cannot deal with cases involving immediate justification, including the anger case. Retreating to INTERNAL PROMPTING* is therefore not a promising move.
I should say that the failure of the standard versions to accommodate cases where we have immediate access to others’ minds is not their only problem. Proponents of the standard versions usually hold that we only have behavioral evidence about others’ minds. However, while behavioral evidence is important, we should not overestimate its importance. We arguably have non-behavioral evidence about others’ minds. Consider the following case. Skimming through the latest summary of new articles in my journals sent by PhilPapers, I find that your partner has a forthcoming article in a top journal. Given my background information about how much you want your partner to get published, it seems that I have justification to believe that you are happy and do so without observing your behavior.
Cochrane (2021) describes this case differently. He thinks that it is Tatiana who first feels the headache and it is Krista who reports “My sister has a headache.” But note that immediately after one twin reports “My sister has a headache,” their grandfather touches Krista, and the same voice reports “Don’t touch my sister” (Pyke, 2017, 12.24–12.28). It is more likely that it is Tatiana who makes these reports. So while I agree with Cochrane that it is hard to tell from the documentary, I will stick to my description of the case.
In my usage, “experience” can denote parts of single encompassing conscious states of subjects at a time. One might instead use “experience” to denote those encompassing conscious states. On this line of thought, the twins’ case needs to be restated in terms of which parts of experiences are shared. For convenience, I will stick to my usage.
I assume that one has immediate justification from one’s pains to believe that one is in pain, and that the twins are no exception to this rule. I will come back to this below.
Compare the case where the twins fall while sledding. Since Tatiana feels a pain in her bottom that hurts, she has justification from her pain to believe:
HURT 1: I feel a pain in my bottom that hurts.
When combined with LINK, Tatiana’s pain gives her justification to believe:
HURT 2: Krista feels a pain in my bottom that hurts.
Krista later reports that she felt it but it did not hurt. Krista’s testimony defeats Tatiana’s justification to believe HURT 2 without defeating Tatiana’s justification to believe LINK.
What the nature of the sense of mineness is and whether there is such a sense are matters of controversy. For discussion, see the papers in the special issue edited by Farrell and McClelland (2017) and Guillot and García-Carpintero (forthcoming). For a survey of cases of loss of the sense of mineness, see Klein (2015).
On Klein’s (2015) view, when the twins share an experience, only the twin in whose body the experience originates is aware of it as her own. Commenting on Krista’s ability to report what Tatiana has in her hand without seeing or touching it and to point precisely with her eyes covered to the spot on Tatiana’s body where she was being touched, Klein says:
[Krista] can correctly attribute shared experience (e.g., feeling of possession, feeling of touch) to her sister (and Tatiana can do the same). That is, the twins correctly ascribe occurrent mental states to the person in whom the states originated. [Krista] does not say “I have a toy bird” or that “I have been touched”; rather, she says that Tatiana has the toy bird and Tatiana has been touched (p. 367).
Klein only cites Dominus (2011). But, as we saw, Pyke’s (2014; 2017) documentaries show that the twins ascribe shared experiences to themselves even when the experiences do not originate in their bodies. So it seems more plausible that when they share an experience, each is aware of it as her own, whether or not it originates in her body.
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Thanks to Shaun Nichols, Derk Pereboom, Nico Silins, and two anonymous referees for their comments on earlier versions of this paper.
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Kang, SP. Shared consciousness and asymmetry. Synthese 200, 413 (2022). https://doi.org/10.1007/s11229-022-03890-w
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DOI: https://doi.org/10.1007/s11229-022-03890-w