Now we're drawing close to the metaphysical
lock. The material of this chapter will walk us right to it.
An extended quotation from William James' Principles of Psychology
introduces the concept of
the "stream of thought." James will preface this germinal and perennially popular
concept with a treatment of
"time-gaps"; first treating time-gaps which are not perceived during
the conscious daylight hours, and then dealing with time-gaps which are dimly
perceived upon waking from sleep. James' recognition of time-gaps, and the
mind's ability to maintain continuity in spite of them, long ago raised this
treatise to the status of a landmark in the history of psychology.
As we advance into this chapter we will orient
ourselves continually by James' trusted landmark.
Here is the stream of thought, as first argued in William James' 1890 masterwork, the Principles of Psychology:
Personal Consciousness, Thought is Sensibly Continuous
I can only
define 'continuous' as that which is without breach, crack, or
division. ...The only breaches that can well be conceived to occur
within the limits of a single mind would either be
interruptions, time-gaps during which the consciousness went out
altogether to come into existence again at a later moment; or they would be
breaks in the quality, or content, of the
thought, so abrupt that the segment that followed had no connection whatever
with the one that went before. The proposition that within each
personal consciousness thought feels continuous, means two things:
1. That even where there is a
time-gap the consciousness after it feels as if it belonged together
with the consciousness before it, as another part of the same self;
2. That the changes from one moment
to another in the quality of the consciousness are never absolutely
[In an earlier chapter] we saw that
such time-gaps existed, and that they might be more numerous than is usually
supposed. If the consciousness is not aware of them, it cannot feel
them as interruptions. In the unconsciousness produced by nitrous
oxide and other anaesthetics, in that of epilepsy and fainting, the broken
edges of the sentient life may meet and merge over the gap, much as the
feelings of space of the opposite margins of the 'blind spot' meet and merge
over that objective interruption to the sensitiveness of the eye. Such
consciousness as this, whatever it be for the onlooking psychologist, is for
itself unbroken. It feels unbroken; a
waking day of it is sensibly a unit as long as that day lasts, in the sense
in which the hours themselves are units, as having all their parts next to
each other, with no intrusive alien substance between. To expect the
consciousness to feel the interruptions of its objective continuity as gaps,
would be like expecting the eye to feel a gap of silence because it does not
hear, or the ear to feel a gap of darkness because it does not see. So
much for the gaps that are unfelt.
felt gaps the case is different. On waking from sleep, we usually know
that we have been unconscious, and we often have an accurate judgment of how
long. The judgment here is certainly an inference from sensible signs,
and its ease is due to long practice in the particular field. The
result of it, however, is that the consciousness is, for itself, not what it was in the former case, but interrupted
and continuous, in the mere time-sense of the words. But in the other
sense of continuity, the sense of the parts being inwardly connected and
belonging together because they are parts of a common whole, the
consciousness remains sensibly continuous and one. What now is the
common whole? The natural name for it is myself, I, or
and Peter wake up in the same bed, and recognize that they have been asleep,
each one of them mentally reaches back and makes connection with but one of the two streams of thought which were broken
by the sleeping hours. As the current of an electrode buried in the
ground unerringly finds its way to its own similarly buried mate, across no
matter how much intervening earth; so Peter's present instantly finds out
Peter's past, and never by mistake knits itself on to that of Paul.
Paul's thought in turn is as little liable to go astray. The past
thought of Peter is appropriated by the present Peter alone.... He remembers his own states, whilst he only conceives Paul's. Remembrance is like direct
feeling; its object is suffused with a warmth and intimacy to which no
object of mere conception ever attains. ...[W]hatever past feelings
appear with those qualities must be admitted to receive the greeting of the
present mental state, to be owned by it, and accepted as belonging together
with it in a common self. This community of self is what the time-gap
cannot break in twain, and is why a present thought, although not ignorant
of the time-gap, can still regard itself as continuous with certain chosen
portions of the past.
Consciousness, then, does not appear to itself chopped up in
bits. Such words as 'chain' or 'train' do not describe it fitly as it
presents itself in the first instance. It is nothing jointed; it
flows. A 'river' or a 'stream' are the metaphors by which it is most
naturally described. In talking of it
hereafter, let us call it the stream of thought, of consciousness, or of
James illustrates with the waking of Peter
and Paul a faculty of the living body which is so much taken for granted as to be
almost beneath comment. This faculty is just the brain's ability to maintain a
stream of thought perpetually, through all the vicissitudes of life.
James speaks of
thoughts as "broken by the sleeping hours." Now, in the interest
of accuracy we should note that modern measurements have shown brain activity to
continue unbroken during sleep. Neural currents never halt entirely: in sleep they only
continue in a mode of passive somatosensory awareness less capable than waking
this fact with supporting endnote as a small caveat. James' illustration still has value for us,
even with this correction affixed.
from the caveat: we read in James' text his awe of the mind's ability to overcome conscious disruptions; not only
the common disruption of sleep, but also the time-gaps induced by anesthesia,
epilepsy and fainting. All these it overcomes by
"knitting" present and past thoughts back into a sensibly continuous
whole, it should be reiterated, is only a
subjective whole. If I might elaborate on James' celebrated treatise:
James understood that the time-gaps which afflict our minds mark off
intervals of time whose reality is independent of our imperfect perception of those intervals. Sleep,
anesthesia, fainting and so forth — these disruptions only cause the mind
to "lose track of time." The duration of
the time "lost" can be measured objectively, with clocks.
But the unconscious mind is ignorant of this objective view, having access to no
clock other than the
subjective, or internal one. When a man "gets his clock cleaned,"
as they say, he may be unaware of the interval of time which passes as he
staggers through a time-gap. Regardless of the extent of the disruption,
from his subjective vantage the stream of thought presents itself
as entirely continuous and whole.
The stream of thought perceives itself as continuous and
whole just because the mind is never more than dimly aware of subconscious and unconscious states. Its lapsing oversight is a
consequence of physiologic limitation, rather than any active power — Table 8.1
confirmed this inference at a phenomenal level. So the perceived
wholeness across time-gaps is only a faculty of inactivity. James' treatise invokes analogous
physiologic limitations by way of an explanation:
To expect the consciousness to feel the interruptions... as gaps, would
be like expecting the eye to feel a gap of silence because it does not hear, or the ear to feel a
gap of darkness because it does not see.
James' Peter-and-Paul illustration stresses the reliability of this
faculty. I'd like to revisit James' illustration and adapt it to the needs of the
As James drew them, Peter and
Paul "forgot themselves" as they slumbered. When they
awoke, they remembered themselves by quickly restoring their distinctive
psychological states (and, by inference, their personal identities).
But what could
we say of Paul were he to suffer a stroke as he slept, losing some memories
as a consequence of epileptic brain damage? Would the injured
Paul wake to the same fullness of self as the uninjured Peter? Probably he
would not. Remembrance in Paul would be weakened, and therefore he would
not know himself so fully as Peter would. Some events of Paul's past would
no longer exist within his consciousness; or, to use James' preferred phrase,
within his "community of self."
Of course, Peter
might thereupon choose to help Paul re-learn those memories which injury had
erased. He could re-educate Paul in the stories of lost events.
But even after re-education, Paul would not, we may think, feel a strong
attachment to events now known only through stories. Paul's regained
memories would not have that "warmth and intimacy" which they had
enjoyed before, when they were undoubtedly his own. (Sadly, this hypothetical state
is only a common element of the deep impairments known from clinical study to be attendant parietal lobe injury.)
But going further: what if Paul's stroke should prove even more
severe? What if it were to entirely destroy
the tissues of long-term memory during a coma blackout, and leave him unable to recall his past upon
waking? In this extreme case his power of remembrance would be helpless to
"reconnect" his past: he would wake as an amnesiac. Upon
waking he would have to discover himself anew, as a new man. And if Peter
were to relate some stories from Paul's past which seemed to the new man
unpleasant or embarrassing, this new man might even be inclined to separate
himself from Paul by changing his appearance
and behavior, or by taking a new name. I'll refer to this transformed man
as "New Paul," in contrast with
"Old Paul," who would be no more.
Looking to New
Paul's future we can see that the only memories which will hold a warmth
and intimacy for him will be those memories recorded through personal
experience after waking. These new memories
will be part and parcel with his new personal identity.
Even so, we might wonder if our Old Paul yet requires
something of the new: some psychological debt to be paid, or vow to be
kept. Let's consider the question from an observer's perspective.
We, being outside observers, can still remember the man whom the new Paul
has forgotten. We know that the old Paul has passed imperceptibly into the
new. Our objective vantage allows us to
see that this passage has happened. And perhaps this inclines us to think
that the new Paul must be obliged to rebuild himself
in the image of the old Paul. This, in tribute to the life that has been
But this opinion
would likely be mistaken. The subjective experience
of New Paul would be no different from Adam's, really. He would
arrive on the scene ignorant of all that exists, not unlike the proverbial First
Man. Since this New
Paul would be, for all intents and purposes, a new man, he would not be under
any special obligation to the old Paul. Old Paul would be to him no more
kindred than any other stranger.
By this reasoning we
may decide, correctly I think, to grant independence to the new Paul. The
body New Paul inhabits should now be his own, even though it had been Old Paul's
before. Likewise, all properties and other assets should
transfer free of obligation. With these tools the new Paul can build a new life.
Perhaps out of courtesy Peter should give this new Paul the option
of living without knowledge of the old.
We'll open a broader
perspective on personal identity by contemplating another, simpler story. I'll present this new story, and then I'll return to
compare it against our story of Old and New Paul. The comparison will
be instructive, I think.
As a fresh
"thought experiment" I'd like to conjure up an Aegean idyll. The
stage for the idyll will be a land set apart from the rest of Creation: it is a quiet meadow.
The meadow is bordered by hills at left and a grove at right; just so:
I'll place some
conditions on the life in this little universe. The land provides life to
plants alone, and to no animals or persons at all. It is a vegetative
cosmos — with one exception: a small house will now open onto the
meadow. It is home to a noble Greek couple: the veteran Nicos and his
wife, Casta. I'll add their house in Figure 9.2.
Here the two live
in calm isolation. They enjoy life as vegetarians, and in peace. For
many years they carry on thus, living without the company of other persons or
animals, for their cosmos contains no other inhabitants.
In time Nicos
succumbs to old age and passes away in his sleep. Casta performs the
rituals in his honor, and being still healthy she lives on in solitude.
This solitude ends nine months later, when Casta gives birth to Nicos' son,
Thanos, whom she had conceived shortly before Nicos' death. Casta will raise
Thanos within their idyllic meadow home.
The Aegean idyll has now
told a spare story of three lives involved in a death and a birth. The
illustration below abstracts those lives into timelines of existence. Each
thick white line symbolizes the temporal extent of a life in the idyll. Time
flows from left to right. We see again that Nicos passes away before the
birth of Thanos, and that Casta lives throughout the full duration of the story.
Timelines for Nicos,
Casta and Thanos
We will come across
this illustration again, later in the essay. For now, we can note that the idyll's text
and imagery present only visible facts of the idyllic
cosmos. The story has not yet spoken to the subjective, interior, reality
of the characters. And this will be the next task: to sketch some
essentials of the subjective experiences of their lives.
The sketch will
incorporate James' ideas, and also the deductions we still hold as our
metaphysical keys. Again, those keys are complete
mortality and the corporeal basis of personal identity.
So, peering first into the
life of Nicos:
His is a robust
soul. By day he enjoys the full powers of mind: an unbroken stream of
thought, subjective awareness, remembrance of a noble life's events, and so forth. Each night heavy
slumber deprives him for a time of these mental faculties and intersperses dim
time-gaps into his rest. Morning follows night,
and the waking Nicos remembers himself by reaching back into his store of
memory, re-acquainting his mind with familiar thoughts and sensations. A sweet breeze off the
meadow stirs thoughts of wife and home, and he awakes.
This is the
daily cycle of Nicos' conscious experience. It continues without
subjective disruption for the duration of his life.
And then, on the
appointed night, Nicos passes away in his sleep. What can be said of his
subjective experience on this night? We can imagine the outline of
it. The night begins like every previous night, with a heavy
slumber. And in that slumber Nicos lives through dim time-gaps. But this night one time-gap does not end with a
restoration of consciousness. Instead the dimly-felt, subconscious time-gap
of sleep descends to an unfelt, unconscious level. There it continues, unfelt,
unperceived, into the hour of his life's cessation; wherein he dies.
As Nicos is
understood to be completely mortal, death entirely unravels his personal identity. It
empties his store of memory and halts the inertial whirl of
subjectivity. At the very end his continuous mesh of neural structures
crumbles, making the loss irreversible.
criteria of personal identity have now failed him. Objectively we see that
his body is no longer animate. We say that Nicos no longer lives.
But to say that Nicos
"no longer lives" is to state a purely objective, external view of
his death. Nicos' subjective, internal view would at this time be entirely
ignorant of the view without. By the understanding we
have developed in previous chapters we can say with good reason that Nicos'
subjective view must be quite different from the objective view — our
modern understanding of personal identity requires this distinction. The
two different views, subjective and objective, do not overlap; and this
fact compels us to consider Nicos' subjective view as a "thing-in-itself," knowable only on its own
Nicos' viewpoint alone, we ignore the outward
appearance of the matter and focus on the purely subjective experience which Nicos
should be expected to encounter. What can we say of the moment when personal
identity finally fails him?
At that moment Nicos' subjective experience is suspended — in toto — by the
functional disruption of death. This suspension is still understood
most readily as an unfelt time-gap.
Nicos' subjective experience of death is thereby reduced to an elemental, which
is just this:
, Nicos' unfelt time-gap
No other subjective
experience would be consistent with James' stream-of-thought psychology.
Nor would another experience square with the
conditions of complete mortality and personal identity.
This particular time-gap
is unusual in that it is open-ended. Nicos' inanimate body cannot restore subjectivity
to Nicos in future; as a result, it cannot end the time-gap which Nicos'
death has initiated.
Hereafter I will refer to this
special type of unfelt time-gap as a "mortal amnesia": it is the
forgetfulness of existence we can associate with failure of the criteria of
personal identity. By prior reasoning this amnesia is irreversible. Having encountered
mortal amnesia, Nicos afterwards lacks the means of perceiving any aspect of his condition,
or of recovering in future any of the memories which death has destroyed.
This is the deepest,
most engulfing time-gap which Nicos can encounter; for here no subconscious or unconscious thoughts
can persist to facilitate his recovery. Mortal amnesia casts Nicos into a state of timeless
imperception that is indistinguishable from the thoughtless existence we ascribe to inanimate
matter — which, indeed, Nicos has now become.
after the death of Nicos, Thanos emerges into the Aegean idyll. Thanos'
birth is the first to grace their cosmos since the loss of Nicos.
encounters his first experience of life: light, noise, and a hard rush of air into
new lungs. His personal identity is still a blank slate. In these
first moments of life his only knowledge is an innate, instinctive
understanding of life's basic needs. But that knowledge is common to all
living creatures — Thanos' unique memory of life
will come in future, as the stream of thought deposits its silt of memories
in his forming mind.
next Section 2 of 3
Chapter 9, Section 1 Endnotes
James' concept is more popularly known by its lengthier
equivalent, the "stream of consciousness." The concept's
enduring popularity is reflected in its common usage. Newman, Baars and
Cho provide a salient example on page 1202 of their cited article
, wherein the
authors refer to consciousness as a "coherent stream of conscious
representations." For a recent (1992) multi-disciplinary defense of James' 1890 stream-of-thought treatise, see
Owen Flanagan, Consciousness Reconsidered
(Cambridge, Massachusetts: The MIT Press) 153-75, Chapter 8.
For a concise evaluation of the Principles of Psychology
Robert Wozniak's online introduction
William James, "The Stream of Thought," The Writings of William James
, ed. John J. McDermott (Chicago:
University of Chicago Press, 1977) 31-33.
Passive awareness of the somatosensory system persists even in deepest sleep, which is why a midnight thumbprick, or a distress of internal organs, will register in the slumbering brain and elicit groggy response. The unbroken neural currents of somatosensory awareness link
especially tightly, without interruption, day and night. Articles exploring the neural basis of
sleep have been collected by Jerome M. Siegel, and are
Functional differences between the waking and sleeping brain are detailed in a good
courtesy of Diana Molavi. For an overview of memory-related activity during sleep, see
Fuster 284-88. For a simulation of memory recall during sleep, see Bin
Shen and Bruce L. McNaughton, "Modeling the Spontaneous Reactivation of
Experience-Specific Hippocampal Cell Assemblies During Sleep," Hippocampus
6:6 (1996): 685-92.
The confirmation is most explicit in the listing of emergent features.
When mental function drops from the highest emergent level of the hierarchy, phenomenal experience invariably lapses.
James, The Writings of William James
A lucid case study of parietal lobe injury can be found in A. R. Luria,
The Man With a Shattered World: The History of a Brain Wound
Basic Books, 1972).