PHL471: Locke on Personal Identity
Locke on Personal Identity
- We are discussing two problems: the unity of the self,
and personal identity.
- The problem of the unity of self is, what makes a person
- The problem of personal identity is, what makes a person
one person over time?
- Locke primarily addresses this second concern.
- This selection from Locke is from his Essay
Concerning Human Understanding, from the 1694 edition.
- Locke begins by noting that when we see an object we
assume it is one object (two of the same kind do not
occupy the same space at the same time).
- His ontology allows for three basic kinds: God,
finite spirits, bodies (physical things). The origin of
the latter two makes for the criterion of its identity.
- Identity in an instant is given: each thing is
identical to itself. Locke thinks that this explains then
identity over time for simple bodies, since in each
instant they are self-identical, as long as there is no
- But for life, for example, perhaps things are
different. A heap of matter is different over time if any
chance is made of it. But an oak tree changes constantly,
but we say it is the same tree. Locke's answer: the tree
continues to be the same one tree as long as it partakes
of the same one life. The continuity of this one life
over time is given by a continuity in organization.
- The same is true of animals: they are a single
organization, continuous over time. They are like
machines in this regard, but that their motivating force
"comes from within."
- Locke does not assume that humans are animals, but he
does say that the identity of a "man," by which he means
the body of a human, is one over time because it is
"vitally united to the same organized body."
- Locke warns us off the intuition of seeing the man in
the soul, and then the body is almost irrelevant: were
"the soul of Heliogabalus in one of his hogs, [no one]
would yet say that hog were a man or Heliogabalus." (S6)
Just so, we would call a completely unintelligent man a
man, and a talking intelligent parrot a parrot -- the
animal nature or man-nature is notdetermined by these
intelligence features (S8) Indeed, Locke wants to separate
the term "man" and "person," allowing that a Cobbler could
get the consciousness of a Prince, and thus become that
person, but he would not be the same man as that man the
Prince was (S15)
- This should make clear to us that we should not ask
"what makes something the same thing?" or somesuch very
general question, but rather, must apply more specific
concepts, like: What makes a substance the same substance?
What makes a man the same man? What makes a a person the
same person? And so on. The concept will determine what
the identity criteria are. (S7)
- A person is "a thinking intelligent being, that has
reason and reflection, and can consider itself as itself,
the same thinking thing, in different times and places;
which it does only by that consciousness whic his
inseparable from thinking" (S9)
- Personal identity is then "the sameness of a rational
being; and as far as this consciousness can be extended
backwards to any past action or thought, so far reaches
the identity of that person" (S9)
- But consciousness is interrupted! But this is not a
problem, since when it resumes it has memory and so
consciousness of its past. If the matter of the body has
changed in the interim this does not matter, since it is
the consciousness and memory, not the matter, that
constitute the person. (S10)
- Note also that the matter does change: someone can
lose a limb, and we still rightly say they are the same
- Can we then switch the thinking substance, and switch
the person? Locke answers this by demanding that we get
an account of thinking substance sufficient to tell us if
it works like matter for the materialists -- that is,
whether you can have the same organization in two
instances of immaterial substance such that they are the
same person (at different times), in the way that you can
have the same organization in two heaps of matter, such
that they are the same animal or plant (at different
- Memory is the important link: Locke rejects the view
for example of those who claim we are reincarnated but
that we cannot remember our past lives. Those were not
our lives then -- that is not the life of the same person.
- Locke also offers a theory of self: self is that
conscious thing that is concerned for itself, as far as
the consciousness extends. The self extends then just as
far in this moment as the consciousness extends; I am not
conscious of the inside of the table, for example, so the
table is not part of myself. (S17)
- We must be careful about the use of "I" and similar
terms: they can refer to a man, or to a person. (S20)
- Are we wrong to punish those who claim not to
remember the crime they committed (e.g., they were drunk).
Locke suggests we are, but that it is expedient to punish
them because we cannot know when their claim is true.