No Such Thing as Too Many Minds

ABSTRACT

Many philosophical views have the surprising implication that, within the boundaries of each human being, there is not just one mind, but many: anywhere from two (the person and their brain, or the person and their body) to trillions (each of the nearly-entirely-overlapping precise entities generated by the Problem of the Many). This is often treated as absurd, a problem of ‘Too Many Minds’, which we must find ways to avoid. It is often thought specifically absurd to allow such a multiplication of conscious subjects, even if we could accept it for physical objects. I consider metaphysical, phenomenological, and moral arguments for this asymmetry, and show that they all fail: many overlapping conscious minds is no more problematic than many overlapping physical objects. Theories that imply such a multiplicity may or may not be true, but they cannot be rejected simply for implying it.

KEYWORDS:

• Consciousness
• Manyism
• Problem of the Many
• Mereology
• Overlap
• Parthood

Disclosure Statement

No potential conflict of interest was reported by the author(s).

Notes

1 For discussion see Unger [1980, 2004], Lewis [1993], Merricks [2001], Sider [2003], Seager [2010], Zimmerman [2010], Blackmon [2016, 2021], Simon [2017], Mørch [2019].

2 Blackmon [2016, 2021] defends the likely reality of multiple overlapping minds for each human being, though he does not use the term ‘manyism’, and leaves open the scale of the multiplicity—he mostly focuses on the overlapping minds of hemispheres and whole brains.

3 This claim about thoughts raises semantic and epistemological challenges distinct from the phenomenological challenges I discuss: see Sutton [2014: 632–36] (cf. Unger [1980: 461–62], Merricks [2001: 103], Olson [2003: 329–31], and Weatherson [2003]). For the record, I consider Sutton’s responses successful, and have little to add.

4 See also Basile [2010: 108ff], Coleman [2014: 34ff], Mørch [2014: 172–75], Blackmon [2021: 49].

5 This claim, that an experience’s subjects are not intrinsic to that experience, does not conflict with the idea that a subject’s consciousness is intrinsic to that subject: it is consistent to hold that my experiences are ‘in’ me, but I am not ‘in’ my individual experiences.

6 Similar remarks apply to Johnston’s personite problem: if personites exist, our moral intuitions grew from engagement with sequences of overlapping, psychologically continuous, person-like beings, and should be formulated appropriately. See Johnston [2017b: 211–14] for a discussion of this type of response, which Johnston claims cannot save commonsense morality, and is still ‘unfairly biased against the personites’ [2017b: 214]. I am inclined to disagree, but this raises complex questions about persistence and survival across time that go beyond what I can address here.

7 As best I know, this applies to all actual conjoined twins: even where two brains are linked by nerve tissue, they are either not overlapping, or overlap only slightly. For discussion of the issues raised by Krista and Tatiana Hogan, the most well-studied pair of craniopagus conjoined twins, see Dominus [2011], Langland-Hassan [2015], Roelofs [2019: 11, 112 fn. 57], Cochrane [2021].

8 Simon [2017: 454] notes that there are also trillion experiences wherever we thought there was one. This is fine: experiences too can be counted by overlap, almost-identity, or functional almost-identity.

9 For some discussion of the ethics of partly-unified, partly-disjoint systems somewhat similar to this, see Churchland [1981: 87–88], Rovane [1998: 141], Hirstein [2008], and Roelofs [2019: 270-94].