In Chapter XXVII of his Essay Concerning Human Understand, John Locke argues for a system of determining the continuity of the person overtime. Locke begins his discussion of what he calls “personal identity”, by distinguishing “the person” between other forms of identity present in an individual human being. He asserts that an identity is an entity that is distinct from its surroundings and has only one origin of existence. He then defines an individual as a composition of three distinct identities: 1) the collection of atoms that physically composes a “the substance” or “the body”; 2) the moving, breathing, and living animal, “the man”; and 3) the reasoning, remembering, and conscious mind that informs a human, “the person”.
Lock argues that we should, and in our common language do, define the identity of the “self”, by using this last identity. Using Cartesian logic, he holds that this self is the entity which one perceives oneself to be– “it being impossible for anyone to perceive without perceiving that he does perceive” (322, B). He also holds that the self one is consciously aware of being is identical – can be said to be the same – as all person one can remember being. He advocates this definition regardless of whether the material or immaterial substance one remembers being is the same as that which he is now. Further, he claims a person is the same as another person, if it “considers[s] itself as itself, the same thinking thing in different times and places” (322, B). And by this he means, that a conscious being is the same person for all of the times it can remember existing, specifically remember thinking and doing the thoughts and actions of that former person. This account requires heavily on the faculties of our memory. I will show that Locke’s argument holds, in light of our improved understanding of memory. But also that this new understanding of memory might shift our idea of our former self from a stagnant to a dynamic entity.
Before he expounds on his idea of personal identity, Locke strengthens his account by rejecting and undermining alternative accounts, specifically accounts that place one’s identity in their animal life, or “immaterial soul”. Locke first addresses our physical body, “the substance”, which he thinks most would agree does not define our personal identity. He defines this “body” as a collection of “particles of matter” which composes the physical characteristics of an individual. He holds that although the arrangement of the particles, or atoms, is not pertinent to their identity, the presence of each is: “If one of these atoms is taken away, or one new one added, it is no longer the same mass or the same body” (320, A). However, he holds that any rearrangement of the particles constitute the same body. By this logic, as we eat, we add atoms to our body; we change the substance which we are. Interestingly. Locke does not invalidate “the substance” as an idea of identity because of this apparent impermanence, but rather because it is intuitively not the self that we perceive.
Lock shows that although we are constantly different substances, we are each but one “man”. He also discounts this entity as a basis for the identity of one’s self. He states the different substances that we are at different times, comprise the same animal, as long as it is held together to sustain to one “common life”. Locke uses the example of an oak tree to illustrate the difference between an organism and a substance. He holds that while a substance is “only the cohesion of particles”, an oak composed of growing and changing branches, leaves and roots, is “an organization of parts in one coherent body partaking of one common life (321, B). He suggests that all forms of life – plant and animal – share this definition, including humans. He goes on to illustrate, however, that the “man” should not be considered parallel to “the person”, because his continuity is not necessary for continued consciousness and contiguous identity.
Locke uses the analogy of the prince and the cobbler to illustrate further his distinction between our identity as a man and a person – and to advocate for the latter as a more useful system of determining identity. In this analogy, he presents two characters a cobbler and a prince. He posits that somehow the past thoughts and memories of the prince suddenly “enter and inform” the body of the cobbler and vice versa. He says that although it would seem evident that the prince is the same man as before, there is still a degree of continuity in the cobbler’s existence. He did not disappear, rather only his immaterial conscious has been transposed. He says intuitively in this scenario we would conceive of the cobbler’s self as not restricted to his animal existence, not in his “body” or “man, but rather with his thoughts and memories.
In the analogy of the cobbler and the prince, Locke brings up a possible alternative idea of identity. He says that one could argue that the soul of the cobbler was now present in the prince, and contiguous with the cobbler before the transfusion. Locke directly addresses and refutes this account – that we are the same person as long as we are informed by the same soul. Locke agrees with the idea that an individual is composed of both material and immaterial substances, and that these are independent entities. But he rejects the notion that we should characterize our account of personal identity simply on this indefinable, immaterial substance – or as he calls it, one’s “numerical soul”. Locke posits that there is no evidence to suggest that one’s immaterial substance is unique or original to that individual. Here, he distinguishes between the conscious of a person, and the substance in which that “consciousness is annexed to”. He believes this to be a substance that is permanent in an individual throughout his life. He believes also that this soul may inform different persons within one individual throughout his lifetime. He leaves open the possibility that this soul may inform different bodies at different times. He states that “there is nothing in the nature of matter why the same individual spirit may not be united to different bodies”. But he claims that regardless if they share the same “numerical soul” they are not the same person unless they share a contiguous consciousness.
He uses the example of Nestor and Thersites at Troy to deliver this point. He says, “…suppose it to be the same soul that was in Nestor or Thersites…this would no more make [Thersites] the same person with Nestor than if some of the particles of matter that were once part of Nestor were now a part of [him]”(325, A). Here he uses a parallel objection to his dismissal of “the substance” as identity. He illustrates that in the same way our physical self’s do not account for our identity, our immaterial substance, whatever that may be, cannot be said to contain one’s self without containing our present continued consciousness. Locke supports this claim by examining the possibility of reincarnation. He argues that if his soul inhabited another a long time ago, he would feel no responsibility for their actions; “For whatever any substance has thought or done, which I cannot recollect and by my consciousness make my own thought and action, it will no more belong to me, whether a part of me [his immaterial or material substance] thought or did it, than if it had been thought or done by any other immaterial being anywhere existing” (328, A). This is the first instance which Locke’s presents his goal in creating his account. He argues that although it may be impossible to understand an identity that is not one’s own, these concept of “person” or “self” should be used as “forensic term[s]” – that allows us to address the concepts of blame, praise, responsibility, and punishment.
He discusses humans’ unique ability to recognize one’s thoughts and actions as their own. He says that through this perception, of our thoughts and ideas, we construct a concept of a self. He believes that this self is a person that is the same as any other person at any time, along as it remembers and recognizes itself as once being that person. In modern psychological research, babies are placed in front of a mirror at a young age. When they are able to understand the entity they observe in the mirror is in fact themselves, they are said to have “self-awareness” or “self-consciousness”. Most of the babies, later in life, probably do not remember this first awareness. Locke would likely argues that this means that these adults – although the same humans– are not the same persons as those infants. He argues that the self holds in it memory all of the knowledge of past thoughts and actions it has done, “Anything united to [the self] by a consciousness of former actions makes also a part of the same self which is the same both then and now”. (328, B). Even considering the same man, Locke argues it is not right to attribute (or punish) an action done outside of this scope of consciousness. Even the actions or thoughts of our same human, or same “immaterial spirit”, are not part of one’s self, unless currently in its recollection. In short, sameness of memory by Locke’s account is metaphysically necessary and sufficient to the sameness of persons. You are “the person” that you remember being in any stages of your life. Regardless of the man or the soul of either in question, you are not any “person” you cannot remember being.
The philosopher Thomas Reid posited a famous objection to Locke’s account of personal identity; by stating that Locke’s account intuitively Is not sufficient. He argues that any valid definition of identity necessarily conveys transitive equality, but Locke’s account this is not the case. Locke posits that you are any person that you can remember being – but Reid points out that the person you remember being, also remembers being different persons, some of which you do not remember. Reid uses the example of a retired general who as a young man was a soldier, and as a boy stole an apple. He asks what if the general remembers being a soldier, but not stealing the apple. By Locke’s account, the general is the same person as the soldier, but not as the boy. However, the soldier does remember stealing the apple, so therefore Locke would say the soldier is the same person as the boy. But, as Reid argues, it is counter intuitive to think that the general is the same person as the soldier, and the soldier is the same person as the boy, but the general is not the same person as the boy; identity, it would seem, need be transitive.
Successors of Locke’s account have offered a solution to the transitivity problem. They shift Locke’s argument from saying that a person is the same as another person only if he can remember being him – to instead say: one is the same person as another if he is connected to the person through memory, either directly or through a chain of persons. For example, if Person A is the same as Person B, he either remembers being Person B, or remembers being a person that remembers being person B. This could only be similarly extended: remembering a person that remembers a person that…etc.
Whether or not Locke would agree with this adjustment is open to debate. At several points in his essay he talks about being different persons throughout one’s lifetime – this would seem impossible using the contemporary method of chain memory, because it would seem that all of one’s persons would be remembered by at least of one’s of their other persons. Regardless of his potential view on the matter, this adjustment creates a credible account of identity that deflects Reid’s objection. Through this adjustment we can examine if Locke’s account is, as he argues, the best tool for determining, forensically, the continuation of one’s self. However, we must first consider the implications of new research in cognitive science that has changed our understanding of memory.
Observers citing advances and discoveries in the cognitive sciences might dislodge Locke’s account on the basis of the “frailty of memory”. As it were, by Locke’s account, the extent to which I am the same as another person is purely a function of my memory. Scientists now tell us memory is itself is partly a function of our mind’s, and likely our consciousness. This is not to say that our memory is purely a function of our will, but rather that our will alters our memory significantly and definitely. It would seem, in light of this information and Locke’s argument, the identity of a person is determined by the thing itself.
Modern cognitive science blurs the distinction many Lockians have made between vertical memories and false memories. Scientists say all memories are constructed by your present mind, and indeed consciousness. The self beyond its current consciousness is a conception that is never truly identical to reality, whatever that may be. In our dreams for example, we change our thoughts and actions of both the past and the present persons that we, consciously, think we are and were. Any successor to Locke’s philosophy could solve this problem by limiting the argument to memories during one’s waking state. However, cognitive science now suggests that our waking minds similarly reconstruct memories as conjures them. We actively construct everything, as we conceive it in our current consciousness, including who we remember ourselves being, and what we did. These reconstructions are invariably falsified if not completely imagined. Professor at Washington University Elizabeth F. Loftus refers to this phenomenon simply as “creating false memories”. She claims that “remembering” involves imagining and thereby reproducing the event in our minds, and in the process constructing what we call our “memory” of them. Our minds have no imprint of events that have happened to us earlier in our lives. We actively construct our memories not by mirroring the events, but rather by remembering the concept we conjured the last time we remembered them. In the process, each time we remember an event we change the specific facts of the episode; and thereby change the identity of our former selves4.
It would seem along with transitivity, an account of identity ought to have permanence. In light of cognitive science’s characterization of memory – that it is malleable – it would seem impossible that a former self could be permanent. Even one’s present conscious, dominated by almost instantaneous “sensory” memory, is subject to construction, and therefore detachment from reality. If you are, (are identical with), who you remember being, and who you remember being is constantly changing, you are, logically, constantly changing. Some might dismiss Locke’s account in light of this evidence, arguing that any concept of identity needs permanence for validity. But let’s purpose that Locke stuck to his guns on this issue. He could argue that our conception of a self may be primarily fictional, but, despite this, it still exists as our conception. In this sense, we may exist in the manner we construct. This concept would parallel the existential idea that our reality is bound only by our choices. Whether or not our lives or thoughts are affected by an outside world, it is worth considering that our identity may be in our own hands. The self may be a fiction, and we may be the authors.
Locke’s goal in identifying the continuity of a person is to decipher the true meaning of our concept of self, and use that definition as a forensic tool, so as to allocate responsibility, praise, blame, and punishment. He stops at several instances to illustrate that to punish a person for something they did but cannot remember, is a kin to punishing a person for the actions of an
 After he shows this, he illustrates that he finds it more probably that our souls are not reused, but our only for our individual consciousness. He states, “I agree, the more probable opinion is that this consciousness is annexed to, and the affection of, one individual immaterial substance” (328, A).
 “First Levels of Awareness as they unfold early in life. http://www.psychology.emory.edu/cognition/rochat/Rochat5levels.pdf
 Reports of cases argued and determined in the Supreme Court of Alabama By Alabama Supreme Court, 2004.
 “Creating False Memories” Elizabeth F. Loftus, Washing University at St. Louis
 “Roughly speaking, the sensory register [the most instantaneous of our memory systems] concerns memories that last no more than about a second or two” Cognitive Skills Determine Learning Ability. Susan du Plessis. Audiblox.