The Price of Parfit’s Relation R
Abstract:
In Reasons and Persons, Derek Parfit famously argues that discussions of survival turn on Relation R,
which is psychological connectedness and continuity with any cause. While I find Relation R plausible as
a criterion of survival over time, I have a hard time believing that any cause is sufficient for underwriting
survival. For, if we accept Parfit’s claim here, then we are forced to accept that one survives in
situations where survival seems wildly implausible (such as in The Branch Line Case). Thus, the project
undertaken here is to retain as much as possible of Parfit’s position on survival over time, while avoiding
these problematic implications.
The difficulty raised by such a project is as follows: if I am to hold that only some causes of Relation R’s
holding are sufficient for underwriting survival, then I must come up with a plausible, non-ad-hoc
delimination criterion for appropriate causes. I here posit the following candidate restriction:
The Functionalist Criterion: In an account of what matters, the right kind of cause is any cause
which preserves the continuity of a particular brain’s functional organization.
The Functionalist Criterion, I contend, is able to avoid the unappealing implications of Parfit’s original
view, while also avoiding counter-intuitive implications of other popular views such as The Brain
Criterion. In the final section of the paper, I discuss what I take to be a few general theoretical reasons
to find my view attractive.
1
The Price of Parfit’s Relation R1
In Reasons and Persons, Derek Parfit famously argues that discussions of survival turn on Relation R,
which is psychological connectedness and continuity with any cause (Parfit 1984). I agree with much of
what Parfit says, but there is one implication that I cannot accept: his conclusion concerning The Branch
Line Case (BLC). This is a substantive disagreement, as I am more confident in my judgment here than I
am of virtually anything – certainly more so than I am concerning any of the commitments that lead
Parfit to his conclusion.
My goal in this paper is to discover just how much Parfit’s view must be modified in order to square it
with my intuition concerning BLC, and whether this modification makes Parfit’s view, on the whole,
more plausible or less so. My central claim is that modifying Parfit’s view in the direction I propose is a
good investment: we will jettison a high-cost belief and in return, take on less expensive commitments.
I
Imagine that teletransporting is commonplace.2 To travel any great distance, one need only step into a
personal teletransporter, press a green button, and then arrive (seemingly instantaneously) at the
desired destination. Pressing the button activates a ‘blueprinting’ mechanism, which records the exact
arrangement of every atom making up a person; this process, while painless, results in the total
destruction of the body. The machine then sends this information to whatever coordinates have been
input, where a similar machine constructs a new body according to the exact blueprint. When the
traveler wakes up, she finds herself in an identical condition as when she left, with an exact replica of
her body, all of her memories, intentions, concerns, etc. (This is The Simple Teletransporter Case, or ST).
Many people think that teletransporting, thus described, would be nothing more than a mode of
transportation; and, assuming that it is reliable, many people would be unconcerned about using it. But
suppose that I attempt to use a teletransporter, and discover, to my dismay, that I haven’t gone
anywhere. After pressing the green button, I walk back out of the transporter. The technician, when
asked for an explanation, tells me that an improvement has been made to the machine. It no longer
needs to destroy one’s body in order to construct the blueprint.
Suppose, now, that I discover that the machine has damaged my heart, and it is certain that I will die of
a massive heart attack within a couple of days. My replica, however, is in perfect health – a fact which
the transporter company hopes will relieve some of my distress concerning my imminent death (This is
The Branch Line Case, or BLC).
This information about my replica would not make me feel better, and my death would be no easier to
handle, given that someone just like me will continue to exist. Whatever concern would be warranted
by the knowledge of impending death under normal circumstances is also warranted here. I contend
that my death in BLC would be just as bad as a normal death.
1
Many of the ideas in this paper have benefited from extensive discussion with and patient commentary by Bryce
Heubner, for which I am grateful.
2
My description of ST and BLC are adapted from Parfit (1984: 199-200).
2
But if this is right, then it seems to follow that an ordinary case of teletransporting is also about as bad
as ordinary death. The only difference between ST and BLC is that the destruction of my original body is
delayed by a day in the latter. But surely this is not relevant to the fact of survival. If I fail to survive in
BLC due to the destruction of part of my body (namely my heart), then surely I fail to survive in ST, in
which all of my body is destroyed. The only difference between the two cases is when my body ceases
to function, and surely this is irrelevant. Thus, I seem driven to the conclusion that teletransportation,
as described in the above cases, is always as bad as death.
II
Parfit claims that the survival of my replica is ‘about as good’ as ordinary survival (Parfit 1984: 201). Of
course, he agrees that this is ‘hard to believe’, and he even admits that he would feel anxious about
using a teletransporter, given the opportunity. However, he claims that his reluctance would be
‘irrational’ since his conclusions concerning the teletransporter cases are entailed by a set of
overwhelmingly plausible principles. Most importantly, Parfit thinks that:
(1) Where question of survival are concerned, what matters is Relation R, which is psychological
continuity and connectedness, with the right kind of cause; and,
(2) In an account of what matters, the right kind of cause can be any cause.3
Psychological connectedness here means the holding of particular direct psychological connections
(memory, intentions, etc), and psychological continuity is the holding of overlapping chains of strong
psychological connectedness (Parfit 1984: 206). These principles reflect a further commitment to
(3) Reductionism, which holds that the fact of a person’s identity over time just consists in the
holding of certain, more particular facts.4
In short, Parfit’s project is grounded on a general belief in the plausibility of a psychological criterion of
‘personal identity’ and the implausibility of all non-reductionists views about persons. Parfit, thus,
thinks that we should be reductionists, and that we should eliminate non-psychological reductive
accounts of persons. Building on several thought-experiments (‘division cases’), Parfit also thinks we
should abandon identity in favor of Relation R, since Relation R contains everything that matters and
applies in more cases than identity. Finally, since there is no principled way to distinguish between ‘the
right and wrong kind of cause’ of Relation R, Parfit claims that we should allow that any cause is
sufficient to implement Relation R.
Given this chain of reasoning, it is unsurprising that Parfit is committed to the bizarre-sounding
judgment about Teletransporter Cases: what matters is Relation R, which holds as well between me and
my Replica as it does between me and myself tomorrow. The cause of Relation R’s holding – namely,
replication – is unusual. But principle (2) tells us that any cause is sufficient. So I survive
3
(1) and (2) are repeated several times throughout Part III of Parfit (1984), but introduced at p. 215.
Parfit ends up endorsing a stronger version of reductionism as well – one according to which the world can be
described completely impersonally. However, nothing in the present argument rests on Parfit’s holding one
version over the other, and so I here use only the less contentious definition (1984: 210-212).
4
3
teletransportation just as well as I survive in normal circumstances. In BLC, my replica and I coexist for a
brief time, which means that there will be a very slight psychological disconnect between us at the time
of my heart attack. But this means only that the existence of my replica isn’t exactly equivalent to
normal survival; it is, however, ‘about as good’.5
In line with Sydney Shoemaker (1997) and John McDowell (1997), I want to acknowledge that Parfit
seems to have gotten a lot right in his account of personal identity and survival. However, I wish to avoid
his conclusions concerning teletransportation. I believe that the most plausible way of avoiding these
conclusions to reject only (2), and to argue that there are no overwhelmingly plausible reasons to accept
it. I accept the arguments in favor of reductionism generally, and in favor of the importance of Relation
R. So, the main point of contention concerns the claim that any cause of Relation R is the right kind of
cause. It is only on the basis of this assumption that his judgment about The Teletransporter Cases go
through. I contend that some ways of causing Relation R to hold are not sufficient for survival.
Specifically, I shall argue that destroying a body and replicating it again is insufficient to underwrite
survival.
III
Parfit himself provides one way of modifying his view. One might, he admits, replace (2) with the
weaker
(2’) In an account of what matters, the right kind of cause is the normal cause.6
Thus, when Relation R is preserved in the normal way (whatever that is), one survives, but when it is
caused by teletransporting, one does not survive. In order to defend this view, one would need to
defend some account of ‘normal’ causation and justify restricting survival to those cases. One way to do
this is to posit that a person is essentially her brain, and so ‘normal’ causation must have to do with
normal brain activity. 7 But at this point, it is unclear why we are talking about Relation R at all. We
should simply advocate The Brain Criterion, according to which a person survives only if a sufficient
degree of her brain survives. Relation R’s importance would then be parasitic on the importance of the
brain.8
5
There is a slight difficulty here, since surviving ‘about as well’ is a notion of degree, and most people think that
survival is all-or-nothing. However, Parfit argues convincingly that, if one is committed to reductionism with
reference to personal identity, then survival is not, in fact, all-or-nothing. It can be the case that I survive perfectly,
pretty well, not much, not at all, or even that it is an empty question whether or not I survive. Since I simply
concede this point to Parfit, I do not discuss the notion at any length (c.f. 1984: 210-213).
6
Parfit calls this The Narrow Psychological View.
7
This is what Parfit calls Nagel’s View. See Parfit (1984: 273-274, 289-297).
8
This justification of The Narrow Psychological View is discussed and rejected by Parfit in Appendix D (1984: 468477).
4
It would be nice if The Brain Criterion were true. For those of us with reductionist tendencies, The Brain
Criterion is initially just as plausible as Relation R. But there are problems. One of them is illustrated in
the following case.9
A mad scientist has perfected an artificial brain. The brain must be installed in 1000 pieces, and
each installation requires several hours (since the artificial ‘neurons’ must be synced with the
exact state of the original neurons prior to transplanting), during which a small piece of an
original brain is cut out and replaced with one piece of the new brain (and during which the new
piece is connected to the original brain in exactly the same way as the original piece had been).
Beginning in January 2007, the mad scientist, unbeknownst to me, has been replacing one piece
of my brain with one of the artificial pieces each night. Earlier this year, he replaced the final
piece. I know have an entirely new, artificial brain (call this The Mad Scientist Case, or MS).
The Brain Criterion would claim that I do not survive the transplantation process. Somewhere between
January 2007 and now, enough of my brain was gone and enough of the new brain was present that I
became a different person.10
But Parfit would find this hard to believe.11 Indeed, I find it hard to believe. At every point in the
transplantation process, it seems undeniable that I survive. People do in fact survive losing small
sections of their brains, and in those cases the pieces aren’t even replaced. If only a small piece is lost at
a time, and it is immediately replaced, restoring full brain function, then on what grounds could we ever
claim that I fail to survive? After the final surgery, Relation R has been maximally preserved, the
structure and function of my brain has been preserved, and there is no discernible difference in my
person either from my own perspective or from anyone else’s. If one were to hold that I do not in fact
survive, then it must be the case that the constitution of the brain matter is essential to survival, and it is
just not clear why anyone would think that.12
So we cannot replace (2) with (2’), because we need a theory that explains why both: (a) I do not survive
in BLC; and (b) I do survive in MS. While allowing that Relation R can be caused in any way yields too
broad a conclusion (it fails with respect to (a)), requiring that Relation R be caused in the normal way
yields too narrow a conclusion (it fails with respect to (b)). We need a restriction on the causation of
Relation R that gets the intuitively right answer in both cases.
IV
I believe a much more plausible candidate restriction is the following:
9
The basic argumentative strategy here follows Parfit’s response to Nagel (1984) on pp. 474-475.
Although, because The Brain Criterion is a reductionist view, there are many places in the middle where it is
indeterminate whether or not I survived. C.f. ff. 4 above.
11
C.f. (1984: pp. 475-476).
12
It should be noted that Searle (1992) seems to think that one could not survive in MS, because the resulting
person would be a ‘zombie’ – that is, would have no conscious experience. I, like Chalmers (1995), find this quite
implausible. As will become apparent below, I follow Chalmers in focusing on the functional organization of the
brain, which means that the particular material constitution is unimportant, so long as organizational invariance is
preserved.
10
5
(2’’) In an account of what matters, the right kind of cause is any cause which preserves the
continuity of a particular brain’s functional organization.
(2’’), thus specified, is a version of (2’). (2’) required of the right kind of cause that it be the ‘normal’
cause, but an ambiguity in the meaning of ‘normal’ led to trouble. In interpreting ‘normal’ as something
like ‘statistical normalcy’, I took (2’) to be equivalent to The Brain Criterion, since there is in fact some
sense in which the continued existence of a particular brain is the normal cause of Relation R’s holding.
But this notion of ‘normal’ is problematic, which is what MS reveals. What is important is not what is in
fact the statistically normal cause; rather, what is important is the normal cause, read as ‘the cause
which preserves the brain’s function’. The possibility of a gradual brain transplant shows us that what
we care about is not the stuff that is the brain – we care that whatever that stuff is, it keeps doing what
it is supposed to do.
MS thus forces us to abandon the language of the brain for the language of the brain’s functional
organization. However, this solves only part of the problem. If the right kind of cause was simply that
which preserves functional organization, then there is no reason that Parfit could not agree.
Teletransportation perfectly preserves functional organization in one sense, since my replica’s brain has
exactly the same functional organization as my brain does. But (2’’) does not require merely the
preservation of functional organization – it requires the continuity of a particular functional
organization. This continuity claim, then, requires of a cause that it preserve the particular functional
system in question. Thus, any cause which preserves the continuity of my brain’s functional
organization is a cause which preserves a particular system – namely, the system that I call mine.
This system is at least somewhat resilient, which is why people are able to survive strokes, brain
biopsies, and the like. While the functional system is altered, the system as a whole is continuous.
Further, if the system is temporarily, mildly damaged, then a repair to the system would bring it back to
a perfectly isomorphic status with the original system. And this, of course, is exactly what happens in
MS. However, the system as a whole cannot maintain continuity through any change. In particular,
total destruction of the system precludes continuity between it and any system, no matter how much
functional similarity exists between the two. Thus, according to (2’’), I do not survive teletransportation
because my brain’s functional system is discontinuous with the functional system of my replica.
V
In discussing (2’), I claimed that, on a natural reading, this implies The Brain Criterion. (2’’), then, looks
like it implies what we might call The Functionalist Criterion, which holds that I am essentially the
particular system made up by my brain’s functional organization. This seems to me a happy outcome,
and I will here note a few reasons why.
First, The Functionalist Criterion does not diminish the need for (1); it just makes good on the need for
an account of ‘the right kind of cause’ of Relation R. The Functionalist Criterion, then, is a restriction on
cases of possible survival. Fulfilling this criterion, though, certainly is not sufficient for survival. We are
6
still able to accept Parfit’s reasoning concerning survival being a matter of degree, and concerning the
likelihood that someone might ‘fail to survive’ within a single biological lifetime. If Relation R holds less
than maximally, then one does not completely survive, even if continuity of a functional system is
preserved. Thus, my account of survival is able to account for the plausibility of psychological theories
like Parfit’s, as it is, to a large extent, Parfit’s theory.
However, because it is not just Parfit’s theory, it is also able to make sense of a different, competing
intuition – namely, the animalist intuition. The reaction against psychological accounts of survival often
rests on a sense that survival must, to some degree at least, depend on the structure underlying our
psychology. If we read this as requiring a material substrate, then we are likely to come up with The
Brain Criterion; but we have already seen that this has problematic implications. The Functionalist
Criterion, however, is still able to account for the basic animalist intuition, without resorting to talk of
the material composition of the brain itself. My view allows us to say that what we are concerned with
in talk of survival is – as Chalmers puts it – that in virtue of which consciousness and experience are able
to arise. And what could be a more natural view?
Finally, the view presented here fits comfortably within broadly functionalist discussions of mind. For
anyone who is inclined to think that something like the functional organization of the brain is a good
candidate for being the mind, then my account entails that in discussions are survival, we are concerned
with the preservation of our particular mind. Such a view seems natural and, given the popularity of
broadly functionalist views, this fit would seem to be a point in its favor.
VI
My view, then, is able to account for strong intuitions concerning: the plausibility of the psychological
criterion of survival, the importance of some kind of structural base of that psychology, and the promise
of generally functionalist accounts of mind.
The psychological theorist, however, is unlikely to be convinced. The problem, one might say, is that
there just doesn’t seem to be any good reason to think we should care about a particular functional
system. We have agreed that the psychological states are important; why should we care how they are
implemented?13
At this point, I think we have reached rock-bottom in the disagreement. According to my view, we
should think the particular system matters because otherwise we are forced to Parfit’s conclusion in
BLC, and that cannot be right. Our intuition in BLC is so overwhelmingly plausible that we should revise
our theory in light of it. But my opponent can simply accept the opposite – that Parfit’s theory is so
overwhelmingly plausible that we should revise our intuition concerning BLC. Although I have
attempted, in section V, to provide additional reasons to take my view to be plausible, I cannot prove
13
I thank Tony Ficarrotta for pushing me on this point.
7
that my position is better. All I can do is to argue as I have – that the price of Parfit’s Relation R is too
high; but that with an independently plausible tweak, we can make it affordable.
Bibliography
Chalmers, D. (1995). “Absent Qualia, Fading Qualia, Dancing Qualia.” In Conscious Experience, Ed.
Thomas Metzinger. Imprint Academic.
McDowell, J. 1997. “Reductionism and the First Person.” In Reading Parfit, Ed. Jonathan Dancy.
Malden, MA: Blackwell. 230-260.
Parfit, D. 1984. Reasons and Persons. Oxford: University Press.
Searle, J.R. (1992). The Rediscovery of the Mind. Cambridge, MA: MIT Press.
Shoemaker, S. 1997. “Parfit on Identity.” In Reading Parfit, Ed. Jonathan Dancy. Malden, MA:
Blackwell. 230-260.
8