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Volume II

Locke and the Great Injustice

by Alec Stratton-Lake




A theory of personal identity must tell us two things.  Firstly, it must give us a necessary and sufficient list of criteria for what it is to be a person, i.e., what distinguishes people from non-people.  Secondly, it must tell us how a person at some given time remains identical to a person at some other time.  In other words, a theory of identity must tell us what is required to be x and what it is to remain x during a period of time.


Discussions about what constitutes a person stretch back to the Ancient Greeks.  John Locke, though, can be seen as providing revolutionary insight on the topic.  Locke separated the identity conditions for humans and persons, and thus attempted to move away from the anthropocentric focus of personal identity that had influenced the discussion of the topic throughout history.  Locke’s theory of personal identity was defined in his work An Essay Concerning Human Understanding.  While Locke has been applauded for his contributions, his supposed conception of personal identity has been almost universally condemned.  Objections to Locke’s theory have been accepted as damning, and the attention of philosophy has moved on.  While some claim that a Lockean train of thought runs through modern conceptions of identity, any real semblance to Locke’s original position has been abandoned.


So where did Locke go so tragically wrong?  On the contrary to any true tragedy, Locke’s mistake is merely semantic, rather than theoretical, as most have thought.  Because of a lack of clarity and his cumbersome use of terminology, many have left Locke’s intuitive, workable theory of personal identity by the wayside.  In this paper I will argue that Locke has been grossly misunderstood, and that Locke’s commentators have been attacking a theory he did not hold and criticising ideas he did not think.  It is necessary, however, to first detail the traditional reading of Locke and its objections in order to frame the subsequent discussion.


The Traditional Locke and his Mistakes


Locke has often been thought to claim that a person is a “thinking intelligent being.”  This idea is born from Locke’s distinction between “man” and “person.”  The reason for this distinction is that our conception of what a person is does not seem to involve a particular kind of body, since we can reasonably attach personhood to anything possessing the ability for rational discourse.  During the discussion between what distinguishes man and person, Locke somewhat strangely uses an example of a particularly intelligent parrot.  In this example, Locke recounts the words of a man who had discoursed with Prince Maurice.  During this encounter, the prince told the tale of his meeting a parrot.  While governing in Brazil, Prince Maurice came into contact with an old and seemingly rational parrot.  When first introduced to the prince, the parrot displayed the ability to converse in a manner that would lead one to believe it to be completely fluent in Portuguese.  While the parrot certainly seemed to be a sarcastic and dismissive individual (the parrot jokes about the prince’s Dutch heritage, and refers to him as some “some General or other”), it demonstrated intelligence comparable to that of humans.  But, one would not then conclude that, because of its intelligence, the parrot is in fact a human.  Such a thought would be ridiculous because the parrot lacks all the physical features characteristic of humans.  It is not, then, rationality that distinguishes humans [“man”] from other animals [“persons”], but rather humans’ unique physical structure.  Given that a human is defined by a particular type of body, the question remains: what is a person? 


The example of the parrot is supposed to engender a likeness between ourselves and the parrot, thus leading to Locke’s more reasonable assertion: what defines a person is not biology, but rationality.  This example brings forth the intuition that our unique psychology is the fundamental component of our personal identity. 


The parrot example can certainly be considered effective insofar as its intuitive appeal continues to be discussed to this day.  But let us move on from explicating Locke’s criterion for personhood.  For one, many might justifiably claim that the traditional account is adequately backed by the text in this area. Further, while the position is hardly free from contention, it is still reasonable.  What I want to focus on, instead, is the range of philosophical consequences of claiming that a person is a thinking intelligent being, and Locke’s criterion for persons to remain identical over time. It is in these two areas that I believe the traditional reading of Locke has misconstrued Locke’s thinking.


The traditional reading of Locke’s criterion for persons to remain identical over time is usually based on such excerpts:


Being … can consider itself as itself, the same thinking thing, in different times and places.


As far as this consciousness can be extended backwards to any past action or thought, so far reaches the identity of that person; it is the same self now it was then.


Consciousness, as far as ever it can be extended—should it be to ages past—unites existences and actions very remote in time into the same person, as well as it does the existences and actions of the immediately preceding moment: so that whatever has the consciousness of present and past actions, is the same person to whom they both belong.


Such excerpts are usually interpreted as Locke speaking about remembrance, wherein “consciousness” is used as a synonym for “memory.”  So, when Locke talks about the extension of consciousness he is really talking about the reach of memory.  If such an interpretation is accurate, then what Locke is saying in these passages is that in order for x at t1 [time 1] to be identical to y at t2, y must be able to remember being x at t1.


There are numerous objections to this theory—too many, in fact, to look at all of them in this paper.  As such, I shall just focus on the objections by Thomas Reid and Joseph Butler.  The reason for my focus on both Reid and Butler is twofold: first, they provide the most famous and widely referenced critiques of Locke; second, their objections continue to shape contemporary formulations of personal identity, which focus, as Locke did, on the psychology of a person.  As such, Locke’s potential to overcome such objections is relevant to today’s discussion on personal identity.


Reid objected as follows: if memory is the sufficient constituent of personal identity, then one  law of logic to which all have assumed personal identity adheres—transitivity—is not in fact applicable.  The law of transitivity states that if x is identical to y, and y is identical to z, then x is identical with z.  The problem is that if personal identity does not adhere to the law of transitivity, then truly absurd results occur.  Reid famously characterised these absurdities with his “Senile General Case.”  In this scenario there is a boy who steals an apple and, thus, receives a flogging.  Later in time there is a distinguished officer who remembers being the boy who stole the apple.  Even later in time there is an old general who remembers being the distinguished officer, but not the boy who stole the apple.  Now, Locke’s theory supposedly states that the reach of your memory is the reach of your identity; thus, the general is the officer and the officer is the boy, but the general is not the boy, since the general does not remember being the boy.  The situation detailed by Reid is obviously ridiculous, and is not something anyone would want to admit as a logical consequence of one’s theory.


Another problem for Locke is circularity.  Butler was the first to note that “consciousness of personal identity, presupposes, and therefore cannot constitute, personal identity.”  Butler’s point is that x can only remember doing some act because x is the same person who did that act.  If x purportedly remembered doing an act, but it was in fact y who did that act, then x would not be remembering but, instead, would merely believe that he is remembering.  Memory thus presupposes personal identity since, for it to be true that you remember doing something, it must be true that you did that thing in the way that your memory specifies.  Because the idea of memory involves personal identity, memory cannot constitute personal identity.  If one was to define personal identity in terms of memory, one would provide a circular definition—for to understand what consists in personal identity, we must understand memory, but to understand memory, we must understand what consists in personal identity!


What we are left with, then, is a theory that is both absurd (insofar as it denies that the law of transitivity applies to personal identity) and circular (since the theory of personal identity assumes that which it attempts to define).  However, I do not believe these objections are reasons to give up on Locke’s account.  While it is evident from what Reid and Butler have established—that a theory which establishes memory as the sole criterion for the persistence of a person is bound to fail—I want to distance Locke from such a theory.  I believe that Locke had something far different in mind than the theory that has been traditionally ascribed to him.  My primary objective is to capture the correct account of Locke’s theory of personal identity.  However, an interesting consequence of my reformulation of the traditional reading of Locke is that it results in Reid and Butler’s criticisms being inapplicable to Locke. 


Locke’s Motivation


If we are going to accurately represent Locke’s thought, it is necessary to adopt a more comprehensive view of Locke’s work.  We should move away from reviewing individual excerpts from the chapter “Identity and Diversity” (the chapter in which personal identity is discussed), and review the chapter as a whole.  The reason for this is that the later parts of the chapter are usually ignored when interpreting Locke’s theory of personal identity. Presumably, the philosophic community has thought these sections to be superfluous.  I think, though, that it is in these very sections that Locke reveals his true motives for including the chapter on identity.  With an understanding of his motives, we can move toward a better understanding of his writings.


Between pages 331-333 (1690 pagination) Locke discusses the idea of people getting their just desserts.  It is important to ask why he does this.  The traditional reading of Locke claims that he is making a metaphysical assertion about personal identity being constituted by memory.  If this is accepted, then it seems inevitable to conclude that by focusing on just desserts Locke is simply exploring the practical consequences of his theory of personhood.  However, it would be a mistake to conclude that Locke is just following a theoretical exercise in order to fully explicate his theory, for that would involve ignoring key terminology that Locke introduces to explain what the concept “person” involves. 


Locke states unequivocally that “person” is a “forensic term”: a term, which, when used correctly, appropriates “actions and their merit.”  If person is a forensic term, then personhood is directly related to the court of law, and its correct usage would be limited to the fields of justice and ethics.  It could be that Locke is just making an offhand remark, which should not be seriously considered.  This is certainly a move that many traditional interpreters would make.  Ignoring Locke’s attempts to limit the application of personal identity to ethical discussions is too dismissive, though, considering that Locke’s explication of personal identity is coloured throughout by moralistic undertones—as seen, in part, by how the majority of his examples used to explain his theory of identity involve the idea of punishment.  For instance, consider Locke’s example involving Socrates.  In this example, Socrates sleepwalks and generally acts as if he is awake when he is asleep.  However, when Socrates wakes he has no memory of the actions he performed while sleeping.  Locke claims that it would be completely unjust to punish the “awake Socrates” who has absolutely no memory of the “sleeping Socrates.” 


This example is an attempt show that true identity does not consist in the identity of one’s body.  This means that Locke is arguing that, because it is unjust for the “awake Socrates” to be considered the same person as the “sleeping Socrates,” they cannot be the same person.  But justice has nothing to do with the criterion for a particular being a certain kind of object.  Justice is an ethical concern, while identity is a metaphysical concern.  Locke’s argument can only be understood, then, if we understand Locke conception of a person as an ethical one, i.e. a conception of a person that is only applicable to the field of ethics.  As such, the idea that “person” is a forensic term cannot be dismissed; not only does it designate the ethical status of the object the term “person” is attached to, but it also limits the circumstances to which the term is applicable.


And, I should note, I understand that it is controversial to claim that Locke’s conception of personhood is ethical, since it greatly limits the scope of Locke’s work on personal identity.  But, at the very least, it must be agreed for the moment that the idea of just desserts is of great importance to Locke in his writings on personal identity, and certainly influences his motive for writing the chapter “Identity and Diversity.”  


With Locke’s motivations more concretely understood, it is possible to determine more accurately which excerpts should be given the most attention.  With ethics playing such an important role in Locke’s thinking through this chapter, contrary to the traditional line of thought, the passages involving just punishment should be held in high regard.  For example, within one such passage, Locke discusses how God will ensure justice: “God; who, as far as the happiness or misery of any of his sensible creatures is concerned in it, will not, by a fatal error of theirs, transfer from one to another that consciousness which draws reward or punishment with it.”  The problem with the traditional reading of Locke is that it cannot make sense of what is being said here.  Locke is claiming that God will protect us from incorrect memories being transferred into our consciousness so that just punishment and reward is ensured.  But under the traditional reading, memory is the sole constituent of personal identity.  The notion of an “incorrect memory” would be a nonsensical one, since everything I remember would necessarily be a part of my past.  If the passage is to make sense, then, there must be something underlying my first-person experiences that is necessary for personal identity in order to ensure that I am punished justly.  The idea that memory is sufficient for the persistence of personal identity is thus ruled out by Locke, himself!


Locke’s Ethos


I am willing to acknowledge that limiting Locke’s claims about personhood to the field of ethics is controversial. I shall thus provide another argument against the traditional reading—an argument that does not rely on a purely ethical interpretation of personhood.  Rather, I shall appeal to the simpler idea that when reading Locke, who was indeed an intelligent individual, one should try to formulate a coherent theory, rather than look for only errors.  Reflecting on the objections listed in the second section above, “The Traditional Locke and his Mistakes,” it is obvious that “memory as the sole criterion for personal identity” is implausible.  For starters, the traditional interpretation looks inaccurate because Locke makes remarks that imply that he also realises the implausibility of memory playing such a role. Locke notes this when criticising the view that personal identity consists in the continuity of thinking substance. Locke states that:


Few would think they had reason to doubt … the same thinking thing would always be present, and as would be thought, evidently the same to itself. But that which seems to make this difficulty is this … there being no moment in our lives wherein we have the whole train of all our past actions before our eye, in one view, but even the best memories losing the sight of one part whilst they are viewing another.


In this passage Locke rejects the idea that personal identity consists in the sameness of a thinking substance because if the same thinking substance was always present, then it would always appear the same to itself.  Therefore, memories would never fade in and out of the mind’s eye.  But, of course, memories are not like this.  It is evident, though, that this objection would also work against the theory that holds that the persistence of personal identity is the continuation of memory.  Personal identity, unlike a memory, does not fade in and out.  It is ridiculous to propose that by forgetting my identity, my relation to some past person can be altered.  If we are to believe that Locke did not realise such things, then interpreting him becomes an exercise in futility.  Essentially, it would be senseless to ascribe to Locke, who was clearly an intelligent human, the very theory that he identified as flawed.


Where Did We Go Wrong?


It is worth asking, seeing that the traditional reading handles Locke’s text so poorly, why it has reached such wide acceptance in philosophical circles.  The main problem for Locke is that he does not use the term “consciousness” unambiguously.  Sometimes Locke is using “consciousness” to refer to memory, and sometimes he is using it to refer to some other mental state.  For instance, Locke often uses the term in the phrase “the consciousness of past actions” or “the consciousness of past life,” as is seen when he writes: “How far the consciousness of past actions is annexed to any individual agent, so that another cannot possibly have it.”


In this context, it is obvious that he is using “consciousness” as a synonym for memory.  But this cannot be the only sense in which Locke uses the word, because, if we attempt to understand Locke’s usage of “consciousness” as synonymous with “memory,” then some of his passages  become nonsensical.  Take the following excerpt for example: “Consciousness … is inseparable from thinking, and, as it seems to me, essential to it: it being impossible for anyone to perceive without perceiving that he does perceive.”  It would simply be misplaced to read Locke as continuing the former sense of “consciousness.”  Looking at the first clause of the excerpt, we could perhaps understand the idea of memory being essential to thinking, for it is difficult to conceive of an organism being able to formulate any kinds of thought with no ability to remember at all.  But the fact that awareness of one’s perceptions is essential for perception itself in no way relates to the notion that memory is essential for thought.  How is the necessity of self-awareness for perception supposed to illuminate us on the relation between memory and thought?


This excerpt is only sensible if we determine that Locke is using consciousness in a more common-sense form.  Instead of remembrance, as Locke makes clear in the second clause of the quote, this “consciousness” is a cognition of one’s own thought, a self-awareness of one’s mental activity.  I believe this to sufficiently demonstrate that it is this conflation of two uses of “consciousness” in his writings that has led to the traditional reading of Locke. 


The Accurate Interpretation


Thus far, I have argued that Locke’s motives for including the chapter on “Identity and Diversity” involved enriching his position on ethics.  To this effect, Locke designates “person” as a forensic term.  The traditional interpretation of Locke cannot make sense of such a conception of a person (cf. the above section), and, as such, it is necessary to leave behind the idea that memory is sufficient for the persistence of a person.


Now, for an object to be a person at any time, it must be a “thinking, intelligent being.”  Later on, Locke further clarifies this by restricting personhood to “intelligent agents, capable of a law, and happiness, and misery.”  It is evident that, by defining a person in this manner, Locke is a making a conscious link between the criterion for being a person and that of being a moral agent.  It could even be said that he is merging the two terms.  Clearly, the need for a deep connection between persons and moral agents is obvious.  Locke’s conception of a person is an ethical one, and only moral agents (i.e. intelligent, self-responsible beings) can follow any code of ethics.


So, how can a thinking, intelligent being x at t1 be identical with thinking intelligent being y at t2?  For Locke, consciousness is the key.  And, let it be known that when I use the term “consciousness,” I am referring to that which, for Locke, is not synonymous with memory.  Locke states that consciousness provides us with a peculiar perspective on our own mental lives.  This perspective is essential to thinking in the same way that it is impossible for one to “perceive, without perceiving, that he does perceive.”  Therefore, according to Locke, x at t1 is identical to y at t2 if they share the same awareness of thought, the same “consciousness.”


The immediate issue that arises from this claim is how we determine what it means for something to share the same awareness of thought.  Unfortunately, Locke is hardly illuminating on this matter.  Presumably Locke does not require a person to have a continued awareness of every one of his thoughts in order to persist through a period of time.  To hold such a view would make it incredibly rare, if not impossible, for a person to persist longer than a few moments.  But, if we are to understand Locke’s conception of a person as an ethical one, then it is reasonable to limit the required scope of awareness to what is of real value to a person in contexts that are the primary concerns for a code of ethics (e.g. situations in which it is relevant to ask whether this is right or wrong).  Continued awareness of fundamental beliefs, powerful desires, important intentions, and so forth, should then be sufficient for the persistence of a person. 


We can see, then, the modern and more reasonable (compared to traditional Lockean theory) take on the psychological approach to identity emerging here. But if it is true that Locke’s thoughts are much closer to those like Garett, Shoemaker, and Unger, why did he not simply state that the persistence of a person relies on the persistence of particular mental phenomena? Why would he frame his thought in terms of awareness?


What I have emphasised repeatedly throughout this paper is that Locke is using “person” as a forensic term. It is a term that, in Locke’s eyes, is supposed to appropriate “actions and their merit” so that persons can be rewarded or punished appropriately. But Locke thinks that one should only be punished for actions that he is aware of having done, for otherwise “what difference is there between that punishment and being created miserable?  This is why Locke speaks of a continued awareness of mental phenomena rather than a mere persistence of these mental phenomena.  He is concerned with only the ethical aspect of personhood.


With all this talk of awareness, it could  be easy to slip  back into the habit of conflating consciousness with memory. It is evident that due to the relationship between consciousness and thinking that it would be impossible to remember something without being conscious. But it is also evident that the converse does not hold true: I can be conscious and not remember something. It would be absurd to suggest that at every moment during which I am thinking, I am at that same moment remembering something.


This, however, is not to say that memory has no part to play.  It would be irresponsible to suggest that Locke reserved no place for memory in the context of personal identity, especially after the amount of references to it within “Diversity and Identity.”  Memory is an aspect of consciousness in the sense that one cannot be remembering something while unconscious.  Thus, memory provides us with the ability to recognise how far back our identity reaches.  If we can correctly remember doing something at t1, then we, necessarily, were conscious at t1.  Further, Locke does not suggest that memory is infallible.  He recognises that due to various factors, “ideas in the mind quickly fade and often vanish quite out of the understanding.”  Remembrance is not a perfect way of gathering evidence of identity, but it is, nonetheless, a reliable one.  Memory, then, plays an important role for Locke, though not the same role as has been assigned by the traditional interpretations.


To summarise, then, my interpretation of Locke is as such: Locke believes that a person is a thinking, intelligent being.  A person at t1 is identical to a person at t2 if there is a persistence of consciousness between times 1 and 2.  And, we can have evidence of this persistence if the person at t1 can remember actions performed by the person at t2.




I have already given my argument for why the traditional interpretation of Locke is unsuitable, but I do not want it to seem as though I am arguing for my view by simply disparaging those who disagree with me. I think there are numerous positive reasons for why this interpretation should be considered faithful to Locke’s intentions. Firstly, and most importantly, this interpretation takes seriously Locke’s consideration of “person” as a forensic term. This is an important consideration since Locke introduces the term to clarify his conception of a person. By emphasising the importance of “person” as a forensic term, the consequent reading limits the scope of Locke’s claims about personal identity to the field of ethics.


Secondly, this interpretation takes into account that Locke used “consciousness” in different senses.  It notes the fact that when Locke uses the term “consciousness,” he is sometimes referring to a certain kind of inner awareness, while at other times referring to the act of remembrance.  Distinguishing between these two senses of “consciousness” is necessary because, aside from the fact that this is an entirely understandable stylistic slip-up, it also renders many of Locke’s passages nonsensical.  Distinguishing between the two senses of “consciousness” also provides clarity to passages that are otherwise needlessly opaque.


Finally, it is reasonable to suggest that when trying to interpret eminent philosophers such as Locke, it is the burden of the interpreter to provide the most workable account of the philosopher’s theory.  To do otherwise would be a great injustice.  My account of Locke meets this requirement by providing a theory that is reasonable, insofar as it is in accordance with the popular intuition that our psychology is an important component of our identity. 


Of course, even a reasonable theory can be inaccurate when it is attempting to explicate another’s thoughts.  Is this interpretation of Locke inaccurate?  Is my interpretation any less vulnerable to the objections directed toward the traditional interpretation?  As memory now  occupies a solely epistemic role, it appears that Reid and Butler’s criticisms miss the mark entirely.  Reid’s criticism that memory cannot constitute personal identity because memory is not transitive is no longer relevant.  Memory is simply an evidential tool, so it does not matter whether it is transitive.  Consciousness is transitive, so it is perfectly reasonable for Locke to attribute the root of personal identity to it.  Butler’s point that the conflation of identity with memory would lead to a circular definition of personal identity again means nothing to Locke since he is not attempting to define identity as a continuation of memory.  


Of course, I am not going to take the position that Locke’s theory of identity is invulnerable to criticism.  Now that a new formulation of Locke’s theory has appeared, new objections will follow.  On the contrary, my point is that such objections should not be focused on questions concerning the metaphysical nature of personhood, but rather the ethical consequences of Locke’s conception of a person.  My hope is that that my reading of Locke’s writings will clear up some misunderstanding.  Although, I also wish for my interpretation to guide further discussion of personal identity toward the ethical issues associated with it.  For it was with the ethical issues concerning personal identity that Locke was truly interested.



Butler, Joseph.  “Of Personal Identity.”  Collected in Personal Identity.  Edited by John Perry. Berkeley: University of

California Press, 1975, 99-106.


Garrett, Brian.  Personal Identity and Self-Consciousness.  London: Routledge, 1998.


Helm, Paul.  “Locke’s Theory of Personal Identity.” Philosophy 54, 208 (1979): 173-85.


Locke, John.  An Essay Concerning Human Understanding.  University Park: Penn State University Press, 1999. 


Loptson, Peter.  “Locke, Reid, and Personal Identity.” The Philosophical Forum 35, 1 (2004): 51-63.


Reid, Thomas.  Essays on the Intellectual Powers of Man.  Edited by James Walker.  Boston: Phillips, Sampson,

and Company, 1855.


Shoemaker, Sydney, and Richard Swinburne.  Personal Identity.  Oxford: Blackwell, 1984.


Unger, Peter.  Identity, Consciousness, and Value.  New York: Oxford University Press, 1990.


Weinberg, Shelley. “Locke on Personal Identity.”  Philosophy Compass 6, 6 (2011): 398-407.


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