Identity, Immortality, Happiness:
Pick Two Shimon Edelman Department of
Psychology, Cornell University Journal of Evolution and
Technology
- Vol. 28 Issue 1 – February 2018 - pgs 1-17 Abstract To the extent that the performance of embodied and situated
cognitive agents is predicated on fore-
thought, such agents must remember, and learn from, the past to predict the future. In complex, non-stationary environments, such learning is facilitated by an intrinsic motivation to seek novelty. A significant part of an agent’s identity is thus constituted by its remembered distilled cumulative life experience, which the agent is driven to constantly expand. The combination of the drive to novelty with practical
limits on memory capacity posits a problem. On the one hand, because novelty seekers are unhappy when bored, merely reliving past positive experiences soon loses its appeal:
happiness can only be attained sporadically, via an open-ended pursuit of new experience.
On the other hand, because the
experiencer’s memory is finite, longevity and continued novelty, taken together, imply eventual loss of at least some of the stored content, and with it a disruption of the constructed identity. In this essay, I examine the biobehavioral and
cognitive-computational circumstances that give rise to this problem
and explore its implications for the human condition. Death is their fate, the gift of Ilúvatar, which
as Time wears even the Powers –
J. R. R. Tolkien, The Silmarillion
(1977), ch. 1 1. A new angle on some old questions Last October, on a trip to the Capitol Reef National
Park, I went on what is regarded
as one of the most rewarding
canyon hikes in Utah:
the Halls Creek
narrows. Halls Creek follows the Waterpocket Fold south through the wilderness, eventually
joining the Colorado
at Lake Powell. About thirteen
kilometers from the trail-head, it enters a spectacular wet narrows. For the next ten kilometers or so, the now perennial stream runs through a deep, meandering gorge,
in places no wider than a couple of meters, hemmed in by soaring walls of red and white sandstone, which frame a narrow ribbon of ultramarine desert
sky high above. I spent the first day trudging with my backpack south along the stream bed and made my camp at the top
of the narrows. In the morning, leaving the tent in place, I bypassed the gorge by an old trail running over
a saddle east of the creek and entered the narrows from below. Every twist of the canyon held a surprise. Will the sandstone cliffs past that pinnacle
be white or wine-dark or banded? Will the next pool be too deep for
wading, forcing me to swim? Will there be minnows in the pool? Will the quicksand
claim my water sandals? Will there be monkeyflowers among the ferns on that wall?
Will I come against an impassable
obstacle – a chockstone or a fall
– and be forced to turn back? I wished that the day would never end, but end it did. As the sun went down and I rounded the last bend of the gorge, my tent came into view and it occurred to me that the next day, instead
of hiking back to the car, I could
do another loop of the narrows. Or could I? As Heraclitus pointed
out long ago, you can’t step into the same river twice. Perhaps
more to the point, “the same you cannot step twice into the river” (Edelman
2012, 178). Let us assume that I kept collecting memories of experiences in the same manner
that I now collect
digital photographs, indexed and ready to hand, and stored in a repository whose capacity is unbounded
(thanks to an unlimited supply of
memory expansion kits). Could my self, when
augmented in this manner – equipped
with something like the Apple Photos
app, but for entire episodic memories,
and incrementally expandable
– keep experiencing the thrill
of novelty, time and again, indefinitely, in Utah or elsewhere? It might be argued that, had I but world enough and time, and a brain wider than the sky,1 that is, indefinite
lifespan as well as bottomless memory, the accumulation of my experiences would eventually
transform my old self, effectively making someone else happy in my stead (as suggested,
notably, by Parfit,
1971). One way to avoid such a disappointing outcome could be to forgo indefinite
expansion of memory, in which case I would sooner
or later be forced to give up some of my past experiences, and with them those aspects of my self that they are part of. Or, of course, I could give up longevity, choosing instead
to remain myself and to be happy, occasionally, for as long as the good life lasts. The argument that I offer below suggests
that the set of choices
that define this predicament is quite general: it applies to humans as well as to any other type of cognitive agent with a similar evolutionary
or design history. Specifically, I will make a case for the conclusion that one of three important
possible attributes of an agent – indefinite lifespan, or
integral identity predicated on cumulative memory, or the
ability to be happy in the moment when experiencing novelty – must be given up. My argument is built on an analysis of the interactions among these three attributes, each of which is key to
understanding the human condition, and perhaps the condition of any future agents
endowed with artificial general intelligence. Two of these attributes, happiness and memory, including the role of the latter
in personal identity,
have been extensively studied in a variety of disciplines, including
psychology, biology, and evolutionary
science, as well as philosophy. The third, indefinite lifespan or immortality, is an attribute that no humans
possess, yet some consider desirable, and perhaps attainable through technology. All three are familiar themes of a multitude of literary works and many philosophical
treatments, a few of which are referred to here. In philosophy, there are ongoing debates
concerning the relationship between memory and identity (Perry 2008b is a useful entry point into that literature), as well as between
immortality and happiness
(e.g., Thom- son and Bodington 2014). A
number of philosophers working in recent decades (e.g., Williams
1973; Momeyer 1988;
Overall 2003;
Thomson and Bodington 2014) have been moved to conclude that immor- tality
should be shunned because it is arguably incompatible with happiness. As Christine Overall (2003, 165) put it, At some point [. . . ]
the immortal person would have fully exploited
all the capacities of his brain
and body. He would arrive at a stage where his finite
brain could not encompass any
more and his finite body could not do or feel any more than they had already. In other words, the
immortal’s physical
limitations would eventually place insuperable
boundaries on his life prospects. While I reach a similar
conclusion, in my argument I attempt
to extend the philosophical treatments of the issues at the intersection of identity, immortality, and happiness by considering also a range
of findings from psychology and other cognitive sciences, as well as evolutionary considerations. To sharpen the argument,
I rely on the following construal of the three key concepts: (1) cumulative, integral
identity, as constituted by the long-term memory for personal
experiences; (2) effective immortality, extending to many times the normal human lifespan, but not concerned with cosmological time scales; (3) transient,
situated happiness, conceived of as the human emotional response to novelty
and discovery in
experiencing the world, and therefore more akin to joy than to life satisfaction (to use a standard
distinction, stated in more detail
below). The rest of the paper is structured as follows. In section 2, I motivate my conceptualization
of identity, immortality, and happiness and locate it relative to certain classical philosophical
treatments of these matters. Section 3 then states the premises for my argument and the conclusions that they imply.
Some possible objections to my framing of the concepts involved, as well as critiques of my conclusions, can be found in section 4. Finally, section 5 offers a personal
view of the implications of my argument. 2.
Background concerning the key concepts It should almost go without saying that the remarks contained in this section and the list of sources cited
are not intended as (nor could they possibly
be) a complete coverage
of the history and the state of the art in the philosophy of memory and identity, or immortality, or happiness. Furthermore, when discussing these
matters, and especially human memory
and lifespan, I assume that technological progress
will at some point
make
memory extension and extreme longevity feasible; quoting Paul Klee (2012, 188), “I have no desire
to show [. . . ] man as he is, but only as he might be.”2 2.1 Memory-based,
cumulative, integral
identity While it seems to be generally accepted that memory plays some role in forming a person’s identity,3 philosophers disagree as to what that role might be (compare,
for instance, Perry 2008a, parts II and III, to Perry
2008a, parts IV and V). My primary interest here is in subjective
experience, because I would like to understand what factors
contribute to my phenomenal selfhood (what it feels like to be me) and to be able to
draw conclusions about happiness, which is of course subjective. Thus, I am less interested in arguments
to the effect that memory is not a reliable
logical criterion for identity (Shoemaker 1959, 873).4
Nor am I concerned with putative logical
attributes of identity such as “immunity to error from misidentification relative to the first
person pronoun,” discussed in the
context of memory by Shoemaker (1970, 270). In light of the contemporary scientific understanding of how the brain constructs the self (e.g.,
Gallagher 2000), and given
how
easily people can be induced
to falsely recall autobiographical events (e.g., Loftus
2003), positing such immunity seems to be as disconnected from my present goals as striving to formulate a foolproof logical criterion for identity. I am thus naturally
driven toward the stance taken by Derek Parfit (1971, 8): “The alternative, for which
I shall argue, is to give up the language of identity.”
This choice leads to what he later
formulated as the “Complex View” of personal
identity (Parfit 1982) (as opposed to what he referred to as the more
widespread, anti-reductionist “Simple
View”). On Parfit’s psychological-reductionist view (which may be compared to the “psychological,” as opposed to “somatic,” approach discussed
by Walker (2014, 165)), a person
is gradually transformed by his or her experiences
and by memories that result from those, so that the
complex and dynamic cognitive structure that is the self changes
over time, until eventually
little or no overlap may remain between
the old self and a new one (see the diagram
on page 24 of Parfit 1971). Following Parfit, I assume that the accumulation of memories makes up a significant and enduring part of the self:5 the narrative self
(Dennett 1991; Neisser and Fivush 1994; Fivush and Haden
2003; Conway 2005), which is distinct from the momentary
minimal or phenomenal self (Gallagher 2000). It is this life-long process of self-construction that John Keats referred to as “soul-making.”6 I call this aspect
of the narrative self the cumulative integral identity
– my take on personal
identity, which I introduced earlier and which serves as premise (6) for my argument,
spelled out in section 3 below. What if such cumulative memory were effectively infinite in its capacity?
(Effective infinity, made possible
by incremental “upgrades” as suggested
in section 1, suffices
for the present purposes.) When combined
with extreme longevity or effective immortality
(see section 2.2 below), the resulting
unbounded build-up of retained experience records would, with time, change the integral identity of the host beyond recognition.
This, of course, would make any further argument against immortality moot. And what if we require that
the lifespan of the person
be short enough
so that there is not enough time for the integral identity to change
too much as more and more memories
accrue? This, too, would trivially
force the argument’s conclusions,
by ruling out immortality in the first place. To
avoid such a trivial resolution of the quandary
concerning immortality, and to keep things interesting,
our only recourse at this point
with regard to memory is to assume
that its capacity is finite. As long as no record
of experience is ever expunged,7
the identity of the host can be considered as integral in the sense
defined here (modulo normal forgetting). Episode
deletion will, however, necessarily result in a change to the host’s identity, of a complementary nature
to the kind of change precipitated by episode
accumulation. Whether or not a deletion
ever becomes inevitable depends
on an interplay of memory capacity, longevity,
and happiness factors, as we shall see in section 3. 2.2 Effective immortality Although Thomson and Bodington (2014) argue that absolute immortality, which requires an inability
in principle for the agent’s existence to be terminated by whatever means,
is the only kind that
is really worth the name, my focus in this paper is on merely “effective”
immortality, or extreme
longevity, as defined earlier. Even, and perhaps especially, this more practical
version provokes the question: is it desirable? This question is precisely the one that I will be in a position
to address (in section 5), after examining immortality in the context of considerations of happiness and integral identity. Effective immortality is commonly assumed, at least tentatively, to be desirable: “[...]there
are considerable advantages
(or at least purported advantages) to being uploaded,
including immortality [. . .]” (Walker 2014,
175). It would seem that the categorically
negative view of immortality on the part of Thomson and Bodington (2014) is due to their focus on an absolute, irreversible
version of this concept. We already saw,
however, that it is impossible to discuss the desirability of immortality separately from the nature of identity: thus, Overall (2003, 155) argues “[. . .] that two key concepts
of being a person or self underlie
debates about whether immortality is desirable and that which
kind of person one chooses
to be is related to whether
one regards immortality as desirable.” With cumulative integral identity, as defined earlier, standing
in for the concept
of “person or self,” I can now proceed to discuss the concept of desirability. 2.3 Transient, situated happiness It seems
reasonable to assume that to be happy is desirable, but what does that mean? Of the many psycho- logical aspects of happiness (e.g.,
Ryan and Deci 2001; Veenhoven 2003; Lyubomirsky et
al. 2005), I am interested here exclusively in the hedonic
variety, which (unlike the cumulative and sustained “life evaluation” component) is transient and situated, insofar
as it is confined to the “here and now.” Note that transient,
situated happiness, or joy in the moment, happens to be an opposite
of boredom, which, according
to the now classical argument
by Williams
(1973), is the eventual fate, and perhaps the bane, of any human-like immortal. Arguably, a life that affords occasional experiences of joy is a good life and it can be pursued as a
middle way between the unrealistic striving for constant joy (Edelman
2012) and a joyless existence
which, if combined with immortality, does not sound at all enticing. Now, a categorically negative valuation
of immortality can be the consequence of an absolutist take on it, as per
Thomson and Bodington (2014, 256): [. . .] However improbable it might be that we would eventually exhaust even our most profound
sources of meaning if we lived forever,
if that is possible (and we see no credible
way to deny it), then it will necessarily occur, given infinite time. This, we take it, is the deep point
behind Williams’ assertion that: “Nothing less will do for eternity
than something that makes boredom
unthinkable” (Williams
1993: 87). Can a more nuanced
position in the matter of immortality and boredom be formulated and defended? In this
section, I have laid out an arguably
more pragmatist take on all three concepts involved
– cumulative integral identity, effective immortality, and transient, situated
happiness. Can this framing of the key concepts, when combined with evolutionary, psychological, and computational (over and above philosophical) considerations, lead to a conclusion that is as unequivocal as that of Williams (1973) and others who hold
immortality to be undesirable? In the next section,
I lay out an argument to the effect that it can. 3.
The argument, leading to a general
principle The argument rests on several premises, drawn from evolutionary theory and cognitive science. Accordingly, it applies to any species of cognitive agents that are subject
to realistic constraints (of the biological or engineering variety) and to evolutionary pressure and that are situated in a sufficiently complex
environment. The statement of each of the six premises below is accompanied
by a
brief explanation and by a small selection of supporting references. 3.1 The premises (1) Forethought confers evolutionary advantage. That forethought or foresight is evolutionarily advantageous has been argued in the past (e.g., Dennett 2003). The likely evolutionary and brain mechanisms underlying foresight and planning
in primates, including
humans, are discussed by Genovesio et al. (2014).
Forethought, supported by various types of
knowledge about how the world works, serves as the foundational theoretical concept in computational psychology (Edelman 2008, section 2.1.3; for an informal overview, see Edelman 2012, ch.2). The notion of predictive coding (which can be derived from the very general information-theoretic principle
of free energy minimization; Friston 2010) has become a key explanatory tool in brain and cognitive sciences (e.g., Rao and Ballard 1999; Wacongne
et al. 2011; Bar 2011; Clark 2013). The capacity
for prediction may also
contribute to the sense
of agency and self-awareness
(Gallagher 2000; Llinás
and Roy 2009). Finally,
it should be noted that the capacity for prediction is extremely general in that it embodies
“a profound connection between the effective use of information and efficient
thermodynamic operation: any system constructed to keep memory about its environment and to operate with maximal energetic efficiency has
to be predictive” (Still et al. 2012, 120604-1). (2) Novelty-seeking boosts forethought
in complex environments. In environments that are large enough to require
exploration, or that change
rapidly enough to require active tracking, an agent that relies on forethought may need to keep extending
and revising the knowledge it has accrued in order to remain competitive. In such environments, a drive for novelty, or curiosity (Schmidhuber 2009), confers evolutionary advantage (e.g.,
Gottlieb et al. 2013).8
Notably, intrinsically motivated learning (Baldassarre and Mirolli 2013)
may outperform learning
driven directly by
“fitness” (that is, outcomes) over evolutionary time (Singh et al. 2010). Novelty-seeking through exploration in the service
of forethought is thus
an evolutionarily grounded
answer to the question posed by Williams (1973, 93): “In general we can
ask, what it is about the imaged activities of an eternal life which would stave off the principle [sic] hazard to which
EM9 succumbed,
boredom.” (3) Happiness, like other
emotions, evolves
to regulate behavior, including
exploration. The critical
role of emotions in regulating cognition
and behavior is well-documented (Roseman 2008; Winkielman et al. 2011;
Lindquist et al. 2012; Inzlicht
et al. 2015). With regard in particular to happiness,
agent-based simulations of evolutionary dynamics
(Gao and Edelman 2016a) and reinforcement
learning (Gao and Edelman 2016b) suggest that a proper balancing
of the two main components
of happiness – hedonic (momentary; joy) and eudaimonic (strategic; life satisfaction)
– is needed for optimal performance. In a foraging task, where exploitation
must be combined with exploration, agents whose
outcomes are linked to motivation via a well-tuned combination of momentary and longer-term “happiness” explore their territory and accrue fitness
faster than agents that are
motivated directly and exclusively by outcomes
(Gao and Edelman 2016a, 2016b). When considered together
with the evolutionary value of intrinsic motivation (Singh et al. 2010; see premise (2)) and with the cognitive and experiential benefits
brought about by the feeling of
awe stemming from exposure
to striking natural vistas10 (Rudd et al. 2012), these computational studies of happiness offer some intuition as to why traveling to new places (over and above experiencing abstract novelty) makes people feel good, for a while
(hence the term transient situated happiness). (4) As a motive
for exploration and a mediator
of reward, honed by evolution, happiness is only effective when experienced episodically, rather
than constantly. Because of hedonic adaptation (e.g., Lyubomirsky et al. 2005; Leventhal
et al. 2007), no reward can remain of constant value if it is always available
and no drive can remain
equally effective if it is constantly present (Edelman 2012, ch.7).11 It is important to realize
that hedonic adaptation is merely
a manifestation of the
universal physiological phenomena
of adaptation and habituation. Hedonic
adaptation is a valuable
trait: a species whose members are too easily
satisfied with their performance and remain satisfied for too long after success is likely to be at a disadvantage relative to a species that is less prone to rest on its laurels.
Indeed, evolutionary simulations suggest that agents in which hedonic
states decay too slowly are more likely to go extinct (Gao and Edelman
2016a). (5) The memory
capacity of any cognitive
system is finite. This
is one of the aspects
of what philosophers of mind have called our “finitary predicament” (Cherniak 1986;
Harman 1986).12 In mammals,
the capacity of long-term memory likely depends on the volume of the
isocortex, which is thought to be “used up” as new memory traces are laid down over the lifetime
of the individual (Merker 2004). Even if artificial expansion of memory capacity
becomes possible, it should be noted that having a larger memory may negatively affect
cognition. Because working
memory, contrary to the popular notion, is not a dedicated “storage register” but a physically distributed emergent function that piggy-backs on long-term memory
(Ma et al. 2014), a larger long-term capacity
may interfere with flexible short-term use; this, in turn, may lead to a drop in fluid intelligence and to reduced cognitive
performance (Wickelgren
1997; Gray et al. 2003; Conway et al. 2003). Moreover, certain purely
computational considerations suggest
that larger memory capacity
may result in poorer generalization (Tannenbaum,
Yeshurun, and Edelman 2009), further impairing cognition. (6) Identity is constituted in part by cumulative life experience. Episodic memories
accumulated over a lifetime – some repeatedly ruminated
over, some distilled
into concepts and narratives, many distorted to fit preconceptions, most
pushed into the subconscious background – are such stuff as predictions are made on (Edelman 2008, ch.6). As discussed in section 2.1 above, they are also the stuff that makes up what I refer to as cumulative integral identity. With this final premise in place, I proceed to draw the conclusion. 3.2 The conclusion drawn from premises (1)–(6) An agent whose performance depends on forethought (premise
(1)), with a concomitant
built-in drive to
novelty (premise (2)), is faced with a problem. On the one hand, because novelty seekers who are bored
lack situated happiness (premise (3)), and because
happiness can only be attained
sporadically, via an open- ended pursuit of new experience (premise (4)), reliving past positive experiences soon loses its appeal. On the
other hand, because the experiencer’s memory is
necessarily finite (premise (5)), longevity and continued accumulation of novel experiences, taken together, imply eventual
loss of some stored content, and with it
a disruption of the constructed identity (premise (6)). Consequently, for a situated agent, an effectively
unlimited life span implies an eventual
impossibility to both preserve the integrity of its identity
and to be happy in the sense
defined earlier. If such an agent opts for integral identity
– and if it is forever safe, well-
fed, personally attached,
socially integrated, occupationally fulfilled, and
satisfied with its achievements
and status – its existence
may include much contentment, but it will have little joy. 3.3 The Rufus Trilemma The
above conclusion points to a general,
broadly applicable principle: THE RUFUS TRILEMMA.13 Humans – or any other species of sentient agents, natural or artificial, with similar cognitive make-up and
evolutionary history (or design parameters) – may attain at most any two,
but not all three, of the following: ·
integral identity; ·
situated happiness; ·
effective immortality. In the next section, I consider some of the possible objections to the assumptions on which the Rufus 4.
Some possible objections The
comments here are grouped into
three sections, corresponding to the three clauses
of the Rufus Trilemma, followed by a discussion of the limiting assumptions on which it rests. Note that this discussion complements and extends the comments that I made earlier, in section
2, on some of the relevant philosophy. 4.1 Concerning integral identity Integral identity
in the long run need not be limited by capacity. The popular
notion that natural human memory capacity is “virtually unlimited” (as per, e.g., Michaelian (2011), cited above, who in turn cites R. A. Bjork) got a boost recently
with the emergence of the first verified
cases of hyperthymesia
or highly superior autobiographical memory (HSAM; see the references in Patihis 2015).
Like
Funes the Memorious, in the eponymous story by Borges,
people with HSAM remember in great detail an extremely
large number of their life experiences
– an ability that may suggest that human memory capacity as such
need not be an obstacle
to integral identity even in the long run (especially
if some quality of recollection could be traded off for even greater
capacity). Such an interpretation of the HSAM findings is, however,
too simple. For one thing, detailed
investigation shows that HSAM is correlated with the one personality
trait that is the most indicative of the malleability of personal identity: all 20 HSAM subjects available
for the study (Patihis
2015) scored above age-matched controls on trait absorption, defined
as “openness to absorbing and self-altering experiences” (Patihis 2015, 964, my italics).14 If the cultivation
of exceptional autobiographical
memory brings with it a faster rate of personality change,
“capacity” becomes not so much beside the point as simply meaningless, because memory can no longer be considered merely a storage device in the service of an immutable, integral agent. Integral identity
in the long run is infeasible because
of computational complexity, not capacity.
Even if human memory
capacity as such is virtually
infinite, it may still be limited by computational processing (e.g., retrieval) constraints. Thus, Michaelian (2011, 410) claims that “While the necessity
of forgetting cannot be established by appealing to finite storage
capacity, forgetting is indeed
rendered necessary by the
second aspect of the finitary
predicament, limited computational resources.” The considerations on which
this claim is based are, however, uninformed or mistaken. In particular, Michaelian fails to mention the
well-known computational technique of locality-sensitive hashing (e.g., Andoni and Indyk 2008),
which can make retrieval both extremely fast and capable of supporting similarity-based recall. Thus, if the integral identity clause should be dropped from the Rufus Trilemma,
it is not because computational complexity renders it infeasible. Integral identity
in the long run is trivially achievable through memory augmentation technology.
To
a large and constantly
growing extent, our memory storage and management needs are outsourced to external devices. Thus, my notebook
computer holds tens of thousands of images documenting my personal life and travels, as well as thousands of academic papers that are relevant to my work; the sum total of human
knowledge that is distributed throughout the internet at large is also easily
accessible to me. Such artificial augmentation of memory (Burkell 2016)
would seem to obviate
arguments rooted
in human neuroscience. However, as I noted in
section 2.1 (following Parfit 1971), unchecked accumulation of personal memories would eventually
obliterate the person’s original identity. To that, I might now add that, much as external
memory is useful to us, as a repository of personal experiences
it may have the wrong phenomenology. Specifically, computational considerations suggest that a digital system such as an external memory, even if closely coupled to a brain (e.g., via an implant), could never be integrated into its dynamics so as to be experienced naturally
(Fekete and Edelman 2012; Fekete et al. 2016). Until an analogue (as opposed
to digital) substrate for external
memory becomes available,
whose dynamics, moreover, would feel natural to
us, the finite memory predicament will remain an impediment to unbounded integral identity
in the long run. Integral identity
in the long run is undesirable because
forgetting is essential to being human. Much research in cognitive sciences
suggests that memory
is constructive (e.g.,
Koriat and Goldsmith 1996; Glenberg 1997) and that forgetting is essential
to its fulfilling its function, which is supporting decision-making (e.g., Richards and Frankland 2017). On a more philosophical note, Connerton argues persuasively that forgetting is “constitutive
in the formation of a new identity” and that “what is allowed to be
forgotten provides living space for present
projects” (2008, 63). (Burkell (2016) invokes this argument
in support of the
notion that people should have the power
to manage their online “footprints.”) A related notion, expressed
by Mach (1886, 13), is that continuity, not integrity, is central
to personal identity: The ego is not a definite, unalterable, sharply bounded
unity. None of these attributes are important; for all vary even within the sphere of individual life; in fact their alteration is even
sought after by the individual. Continuity
alone is important. Indeed, Mach (1886)
deplores clinging to the ego and envisages a future in which We
shall [. . .] no longer place so high a value upon the ego, which even during
the individual life greatly changes,
and which, in sleep or during absorption in some idea, just in our very happiest moments, may be partially or wholly absent. As I already pointed
out, this view of the nature of the self, just like that of Parfit
(1971), can be seen as an
argument, not against
integral identity, but against extreme longevity (let alone
immortality). Furthermore, just as one may “rebel” against death (e.g., de Unamuno 1972; Momeyer 1988), some of us deplore forget-
ting (Edelman 2014). In particular, I do not think I can credibly claim to have been happy if my recollection of any experience is soon lost, as in anterograde
amnesia (e.g., Mauguière and Corkin 2015), or forcibly
discarded to make room for a new one.15 4.2 Concerning situated happiness Of the two main components of happiness, eudaimonic
and hedonic, the second clause
of the Rufus Trilemma has to do with the latter. The following discussion points pertain specifically to what I previously
called transient situated happiness. Happiness requires identity, as a matter of logic.
Inasmuch as what matters here and now, for me, is my happiness rather than some kind of abstract or disembodied variety (as brought about,
for instance, by a
trance-like experience; e.g., Fischer
1973; Lebedev et al. 2015), it would seem
that happiness is logically
predicated on identity.16
If that is the case, then someone
who picks happiness would be logically required
to also pick identity
(but not the other way around), thereby
upsetting the three-way symmetry
of the trilemma. However, for
this concern to be neutralized, it suffices that
merely a modicum of personal
identity exists
for happiness to be anchored
to; in contrast, in the Rufus Trilemma, the identity in question is integral – not merely a sliding window that retains the recent experiences while letting go of the old ones, but rather the cumulative sum total of one’s experiences over the lifetime. Happiness is not something that humans can reasonably
expect to hold on to. The biobehavioral, and therefore necessarily evolutionary, take on happiness (Buss 2000; Nesse 2004) and psychophysiological phenomena such as hedonic
adaptation, discussed in section 3 are sometimes
used to deflate the exaggerated expectations underlying the “pursuit
of happiness” that characterizes the Western
(and especially American) outlook. The deflationary approach can, however, be reconciled with the apparently universally
human desire to be happy, by focusing on pursuit and forgoing the clinging
that tends to accompany attainment (see Edelman 2012, and the many references therein). Such
pursuit must be at least
occasionally rewarded if it
is to make the pursuer happy, leading us right back to the second clause
of the Trilemma. Happiness can be achieved by means
other than open-ended experiential novelty. This sentiment has often been voiced by ancient
philosophers who elevated equanimity over aspirations (as in “The satisfaction of
contentment is an everlasting competence”; Lao Tze (Laozi)
1904). However, the vaunted equanimity is all about eudaimonia, not transient situated happiness. For the evolutionary reasons
already discussed, we are doomed to seek, in new experiences, fleeting happiness that cannot be found in new possessions17
or new acquaintances,18 let alone in ruminating over the past.19 Happiness should be taken under full control and subjected to reason. It may be possible
to train oneself to forgo both clinging
and striving (and therefore
both the pursuit
of happiness and the happiness
of pursuit), which are perceived as fraught with disastrous consequences by Buddhists (e.g.,
Scharfstein 1998; Siderits 2007). Indeed, technological means for “reaching
in” and modifying the relevant physiological
drives and reward settings
may become available
in the future.20 As Williams (1973,
95) noted, “One might
make
the immortal man content at every moment,
by just stripping
off from him consciousness which would have brought discontent by reminding [my
emphasis] him of other times, other interests, other possibilities.” I have pointed
out elsewhere (Edelman 2012, 67) that doing so would mean becoming
something other than human, setting oneself well apart from the rest of humanity. 4.3 Concerning immortality Immortality is not technically possible, so why fret over purely hypothetical questions? (This question
is worth dwelling on for a moment, even though my argument involves extreme longevity
rather than absolute immortality.) Natural longevity in animals is indeed limited,
probably by more than one factor. In
humans, in particular, “the maximum lifespan
[.
. .] is fixed and subject to natural constraints” (Dong et al. 2016, 257). Intriguingly, in primates the best predictor of longevity is the size of the isocortex, which, as
mentioned earlier, may correspond
to memory capacity
(Merker 2004). What about transcending the bio- logical constraints entirely, by moving the
contents of one’s mind to an artificial system?
On the one hand, because the vehicle/content
(or hardware/software) distinction does not apply cleanly to biological cogni- tive systems, copying a mind would necessitate copying its anatomy and physiology
down to the molecular level.21
On the other hand, a purely functional simulation of a mind, implemented in a digital
substrate (as in “uploading”; Walker 2014), would
necessarily possess radically different low-level dynamics,
resulting in a major disruption (and likely a total obliteration)
of the phenomenal self (Fekete and Edelman 2012). However, while the latter (digital
simulation) route is unsuitable in principle, the former one – recreating
the brain/mind from the bottom
up in an artificial analogue substrate – is merely an engineering challenge, which cannot be dismissed out of hand. Thus, the immortality clause
of the Rufus Trilemma
still stands. Immortality should/will hold no appeal for progressive humans.
This last, normative point has been made
by Mach in the context of his discussion of the mutability of the ego, from which I quoted earlier. The critical step, according to Mach,
is to
recognize that the self is in any case impermanent; “we shall then be willing to renounce individual immortality [. . .]” (Mach 1886, 13). Public opinion
on these matters
varies. Following a survey of the popular culture,
Vidal (2016, 667) remarks
that “Ambivalence is perhaps inherent to issues of longevity and, a fortiori,
immortality. We may be youth-obsessed, and afraid of aging and death,
but
that does not necessarily make
us wish to live forever.” Still, at least some of
us would be unwilling to give up on prospects for immortality just because it seems to others selfish, unnatural, immoral (by religious standards; see Buben 2017) or simply tedious. 4.4 Concerning the scope of the assumptions and the import
of the argument As stated up front in section
1, the argument developed in this paper deals not with identity, immortality, and happiness in general, but
rather specifically with cumulative integral identity, effective immortality, and
transient situated happiness, as defined here. Given the relatively restricted scope of these concepts, the conclusions they afford are also less than general.
As some of the foregoing discussion suggests, relaxing the restrictions – for instance, by settling for (or, in
a design context, opting for) fluid and mutable rather than
cumulative and integral identity
– makes the argument moot. It is conceivable
that certain other changes in the premises
could modify rather than obviate the argument.
For instance, there are good philosophical arguments for the relevant concepts being “matters of degree”
(Parfit 1982, 228) and there is good psychological and biological evidence, as well as computational reasons,
for aspects and faculties
of the mind/brain being rarely if ever categorical (Edelman
2008). This suggests
that the conclusions of my argument may also
be a matter of degree and will hold in proportion to the
degree of integrality, happiness, and longevity,
assumed or allowed. While a restating
of the Trilemma in appropriately graded
terms awaits future
work, in its present form it applies
at least to some of us or some of our progeny, natural or artificial. 5. Concluding remarks Insofar as one must eschew one of the three great
gifts – identity, happiness, and immortality – so as to gain
the other two, the three alternatives that we humans will face in some not-too-remote and technologically
quite plausible future are best labeled by what each of them requires us to give up: integral memory, in favor of happiness
and immortality; or situated happiness, in favor of memory
and immortality; or effective immortality, in favor of happiness and memory. Given how deeply personal this choice would have to be,22 it would be presumptuous to offer any kind of general advice
here. It may be noted, however, that the great
gifts, and the implications of choices that involve them, have long been explored in the literary and other arts. A notion related to these gifts
– that to make the most of the grand gift of life, one must remember, and
be able at will to relive, everything – has also been given a literary treatment
(Edelman 2014). It seems
to me that the choice implicit in this notion
amounts to admitting that the greatest
gift to humans may be not
life, about which those who have been born have no say anyway, but death
– “the gift of Ilúvatar, which as
Time
wears even the Powers shall envy.” Acknowledgments I thank
Eric Dietrich for timely encouragement and for pointing
out to me the connection between happiness and identity; Oren Kolodny for a discussion of
memory, happiness, and hiking; two anonymous reviewers for useful comments;
Russell Blackford for clear, detailed, and extremely helpful
editorial suggestions; and Itamar Edelman
for helping me focus on things that matter. Notes 1. With apologies
to Andrew Marvell and Emily Dickinson. 2.
Here is the quote from Klee (2012,
188) in its entirety: “If I had wished to represent the man ‘as he is,’ I should
have required so bewildering a tangle of lines that a pure treatment of the element would have been out of the question;
there would only have been
an unrecognizable blur. Besides,
I have no desire to show this man as he is, but only as he might be.” 3.
An extreme view
is that memory is “[. . .]
the history that writes the individual,
the narrative that creates the continuity called the person. If memory constitutes the person, then to remember
what was is to be aware of who is, and to remember everything
would be to see the person
in its manifest fullness” (Lopez 1992, 35). 4.
Shoemaker (1959, 873) writes: “Whether or not memory is a criterion of personal identity, it is not the criterion. [. . .] And while
it is true that one does not use bodily identity as a criterion of personal
identity when one says on the basis of memory that one
did something in the
past, this is not
because one uses something else as
a criterion, but is rather because
one uses no criterion
at all.” 5. And, on some philosophical accounts (e.g., Goodman
1978; Putnam 1982),
also of the very world that the person inhabits. 6.
Journal-letter to George and Georgiana
Keats, April 21, 1819 (excerpted
in Strachan 2003). 7.
What I have in mind
here is the kind of forceful deletion
of episodic records
that are central
to the person’s emotional
life, as depicted in the film Eternal Sunshine of the Spotless Mind (2004; written by Charlie Kaufman and directed by Michel Gondry); this is to be distinguished from normal human
forgetting. More about this in section
4. 8.
In the context of the human expansion
out of Africa, it is interesting to consider how in various
populations the distance
from the cradle of civilization correlates with the frequency of an allele associated with openness to risk-taking, found in the gene that codes
for the DRD4 dopamine receptor
(Chen et al., 1999; Matthews and Butler
2011). 9. EM, or Elina Makropulos, is the immortal
protagonist of a play by Karel Cˇapek, discussed
by Williams (1973). 10. Such as those revealed to John Wesley Powell (2003, 397), “sublimity [. . .] never again to be equaled on the hither side of
Paradise.” 11.
Here’s Walt Whitman on transient
situated happiness: “You but arrive at the city to which you were destin’d
– you hardly settle yourself to satisfaction, before you are call’d by an irresistible call to depart”
(Leaves of Grass: Song of the Open Road
82:11). 12.
Michaelian (2011, 407) states it as follows:
“Because her storage capacity is finite, if a human
being were to live for a
sufficiently long time, she would eventually
run out of capacity.” The discussion that follows is,
unfortunately, disconnected from recent and contemporary research in the psychology and physiology
of human memory, resulting
in mistaken claims such as that human
memory has “virtually unlimited capacity.” 13.
Marcus Flaminius Rufus is the central character
in the 1947 short story The Immortal by Jorge Luis Borges (reprinted in Borges 1970). Rufus seeks and gains immortality, only to become disillusioned and weary with his interminable life. Mary Wollstonecraft Shelley’s story The Mortal Immortal
(1829) is likewise built on the premise of immortality becoming unbearable. For additional examples from literature and film, see Vidal 2016. 14. Interestingly, the results
of (Patihis 2015) also highlight the usefulness of memory for prediction. On item #28 on the Tellegen
Absorption Scale (“I often know what someone is going to say before
he or she says it”), HSAM subjects
scored at .416, compared to controls, who scored at .272 (p < 0.01). Likewise, on item #20 (“Things
that might seem meaningless to others often make sense
to me”), HSAM subjects scored
at .594, compared to controls’ .182 (p < 0.001). 15.
Such purging of the mind’s records of experience would amount to acting bulimic, like Emperor Claudius (Crichton 1996), but with regard to memory. 16. This argument has been suggested to me by Eric Dietrich. 17. Experiential acquisitions are known to bring about more enduring satisfaction than material ones (Van Boven and Gilovich
2003); they are also more constitutive of the self (Carter
and Gilovich 2012). 18. For
a study of the role of friendship in happiness, see Saldarriaga et al. (2015).
Momeyer (1988, ch.III) discusses
the repercussions for social
attachment and happiness
of the hypothetical scenarios
in which a person alone,
a group of people, or everyone attains immortality. 19.
Killingsworth and Gilbert (2010),
whose subjects reported
being less happy when caught with their mind wandering
as opposed to when being focused
on the task at hand, quote Keats: “Where but
to think is to be full of sorrow” (“Ode to a Nightingale,” line 27). 20. As they have in science
fiction, e.g., in Greg Egan’s novel Permutation City (1994). 21. I gloss over the fact that the question of the proper
level here remains
essentially unresolved (Fekete et al. 2016). 22. It would be interesting to see how people’s choice
in this matter
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