Human Beings Have No Identical Self
Classic Philosophical Questions Part 6 - Metaphysics
David Hume, from A Treatise of Human Nature
Kem Stone - 2 March 2008
If a stranger approached me and told me that he could convince me that I have no self, I would think this a
hopeless endeavour.  The idea that I have a self seems so certain and incontrovertible that it would never even
occur to me to doubt of it.  Yet David Hume, the same great sceptic who forced me to doubt the relation of cause
and effect, also provides an argument to make me seriously reconsider my notions of self, and whether or not this
is just an abstract idea without reference to any real phenomenon.  I ultimately reject Hume’s argument, but I will
forever be aware that he could be right, and the sense I have that I have been the same fundamental thing
throughout my entire life may be a mere illusion.

Hume acknowledges that we have this idea, that of a self which feels the continuance of its own existence through
the passage of time, but asks a question that few of us consider: from what impression do we derive this idea?  “It
must be some one impression that gives rise to every real idea.  But self or person is not any one impression, but
that to which our several impressions and ideas are supposed to have a reference” (404).  An impression that
gives rise to the idea of self must be continually the same throughout the course of our lives, as this is the nature of
self.  However, it would seem that there is no such impression—that all perceptions are particular, separate and
distinguishable from each other, without any need for something constant to support them.  Through the process of
introspection I come across perceptions of heat or cold, light or shade, love or hatred, pain or pleasure and so on,
but I never directly perceive my
self at any time.

Mankind is then nothing more than a collection of different perceptions which rapidly and perpetually succeed
each other.  “The mind is a kind of theatre where several perceptions successively make their appearance, pass,
repass, glide away, and mingle in an infinite variety of postures and situations” (405).  We may have a natural
propensity to imagine a
simplicity in a perception at one time, or a common identity among different perceptions
at different times, but we have only a succession of perceptions without the slightest notion of the thing to which
these are presented or of the materials of which it is composed.

The question Hume now asks is what accounts for this propensity to ascribe a common identity to these
successive perceptions.  Hume’s analysis consists of two basic ideas that we have: first, of an object that remains
invariable through a duration of time, or what we call
identity or sameness; second, the idea of several different
objects existing in succession and connected by close relation, or
diversity.  Though these are distinct ideas,
Hume claims, it is a common error of our thought to confuse them with one another.  “That action of the
imagination by which we consider the uninterrupted and invariable object, and that by which we reflect on the
succession of related objects are almost the same to the feeling…the relation facilitates the transition of the mind
from one object to another, and renders its passage as smooth as if it contemplated one continued object” (405).  
This resemblance is the cause of the mistake, and our propensity to make this mistake is so great that we
inevitably yield to it and assert that different related objects are in fact the same, and to justify the absurdity we
attribute their sameness to a new concept that we imagine has the necessary continuance to make invariable and
uninterrupted these highly variable and interrupted perceptions—concepts such as
soul or self.

What makes Hume’s claim regarding the nature of personal identity so important is that unlike the arguments of
other philosophers such as Locke, the heart of the problem is not merely language or the terms we use to describe
the idea, but the nature of the thing itself.  When we attribute personal identity to variable and interrupted objects,
we actually commit a metaphysical error by assigning to these objects something that is invariable and
uninterrupted when this is in fact the opposite of their true nature.  When we hypothesise a self or soul to connect
these disjoined perceptions, we create a fiction which stands in contradiction to the truth.

To understand truly what is meant by personal identity, Hume asks whether it really binds the train of different
perceptions together or merely associates the ideas of them in the imagination.   In other words, when we consider
identity are we thinking of a real bond among perceptions or do we merely feel that one exists?  To address this
question Hume appeals to another of his famous arguments, that the relation of cause and effect is never directly
observed in the understanding, but is merely an idea that results from a customary association of ideas.  “For
thence it evidently follows that identity is nothing really belonging to these different perceptions, and uniting them
together; but is merely a quality, which we attribute to them because of the union of their ideas in the imagination
when we reflect upon them” (406).  Our idea of identity is a result of three basic relations: resemblance, contiguity,
and causation.

Hume asks how these relations give rise to the idea of an uninterrupted progress of thought.  He disregards
contiguity because it has little influence on the present matter, and first turns to resemblance, asking us to imagine
that we could see into the mind of a man and observe the succession of perceptions within it.  Supposing he
preserves his memories well, it is evident that this is the only connection we would be able to discern among these
perceptions.  Memory, says Hume, is nothing more than a faculty by which images of past perceptions are
brought to the mind, and “as an image necessarily resembles its object, must not the frequent placing of these
resembling perceptions in the chain of thought convey the imagination more easily from one link to another, and
make the whole seem like the continuance of one object?” (407)  In this case memory alone constitutes the
resemblance which gives rise to the idea of personal identity.

Turning to causation, Hume imagines a person as a kind of republic or commonwealth wherein the members are
all tied into and subordinate to the government, the members being different perceptions and the government being
what links them together by the relation of cause and effect as each produce, destroy, influence and modify each
other.  Just as the same republic may change its members, its laws and its constitution, an individual person may
vary in character and disposition while keeping the same identity.  In this case, personal identity also depends on
memory, as only through memory can one become conscious of causes and effects.

Memory therefore seems to lie at the heart of personal identity, yet a problem still remains.  Once the chain of
causation has been acquired from memory, we can extend this chain beyond our memory.  Circumstances we
participated in but no longer remember can still be attributed to our identity.  “In this view, therefore, memory
does not so much
produce as discover personal identity, by showing us the relation of cause and effect among
our different perceptions” (408).  Due to this and the other difficulties, Hume concludes that all of the subtle
questions regarding personal identity can never be completely decided.

Hume has indeed shown that there are reasons to be sceptical about the existence of the self and our answers to
the questions of personal identity, but when considering the issue from a pragmatic standpoint it seems that such
ideas are indispensable.  Even if the “self” is just an illusion caused by the linking of past perceptions through
memory, it is a useful illusion.  The consequences for ethics, for instance, should we abandon this notion, would be
catastrophic.  We can not justifiably hold anyone accountable for past actions without there being something
constant and invariable within that person which deserves punishment now for an action done previously.  If the
idea of a constant, invariable identity that remains the same over time is in fact a fiction, then we are all different
persons from one instant to the next.  I am not the same person I was when I began writing this text.  I am not
even the same person that I was when I began writing this sentence.

But putting pragmatic considerations to the side, there are still very good reasons to believe in the existence of the
self.  Hume looks at what is separate and disconnected and challenges us to prove that something exists which
binds them together.  But we can just as easily look at everything that has ever been present in our awareness,
understand that by having been present to our awareness they
are connected, and challenge the sceptic to prove
that there is no connection.  He may be able to do this if memory was not continuous, as in the case of amnesiacs
or people with other mental disorders, but most human beings can remember every part of their lives.  Although
we may not remember every detail of every instant we have experienced, we remember
that we experienced
these things.  When I use the word “I” now I am referencing the same thing that I would have referenced when
using the word “I” at any point in the past.  This “I”, the mysterious yet indubitably real subject of all our
experiences, can justifiably be called “self” and as far back as the memory of this self extends, we can attribute
one singular personal identity.  Whether this phenomenon is real or merely apparent, it is real enough in the
understanding of anyone with consciousness and memory.