Thomas Reid held a direct realist theory of memory. Like his directrealism about perception, Reid developed his account as an alternativeto the model of the mind that he called ‘the theory ofideas.’ On such a theory, mental operations such as perceptionand memory have mental states—ideas or impressions—astheir direct objects. These mental states are understood asrepresentations that encode information about their causes. The mindis directed towards and reads off from these representations,information about extra-mental items. By contrast, Reid holds that thedirect objects of memory and perception are extra-mental. In the caseof perception, the mind is directed to present material objects andproperties; in the case of memory, the mind is directed towards pastevents to which the person was agent or witness. In other words,according to Reid, when we remember, we do not recall previousexperiences. In memory, the mind is directed neither towards apreviously experienced idea nor towards an idea of a previousexperience. Rather, we recallevents, experiencedpreviously.

Reid is interested in the notion of memory not only for its own sakebut also because of its conceptual connection to the notion ofpersonal identity. Reid criticizes Locke’s theory of personalidentity for inferring a metaphysical hypothesis now called the MemoryTheory from the conceptual connection between memory and personalidentity. On this theory, personal identityconsists inmemory; sameness of memory is metaphysically necessary and sufficientfor sameness of persons. According to Reid, memory is neithernecessary nor sufficient for personal identity, metaphysicallyspeaking. Indeed, Reid holds that it is impossible to account forpersonal identity in any terms other than itself. Personal identity issimple and unanalyzable. Though memory is not the metaphysical groundof personal identity, according to Reid, it provides first-personalevidence of personal identity. I know that I was present at mygraduation because I remember being there. Memories do notmake one the same person over time. Rather, memories allowone to know one’s own past, immediately and directly.

• 1. Criticizing the Storehouse Model of Memory
• 2. A Direct Realist Theory of Memory
• 3. Objecting to Locke on Personal Identity
• 4. Personal Identity as Simple and Unanalyzable
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1. Criticizing the Storehouse Model of Memory

Reid traces the target of his criticisms back to the Ancients, whom hedepicts as holding that the mind is a sensorium—a repository ofpast ideas and impressions (Essays, 280).^[1] On this theory, perception, memory and imagination are causalprocesses beginning with purely physiological events: impressions onthe brain. These physiological states are taken to have mentalcorrelates—sensations or ideas of sense or senseimpressions—which are the objects of perception, memory andimagination. These ideas or impressions are representations in thesense that they preserve, or re-present information from theirphysiological correlates. According to Reid, this view recognizes nodistinction between imagination and memory. Each consists in having apicture-like impression that remains after the object that impressedupon the senses is gone. The only difference between the two is in thefidelity of the imagistic impression to its cause. Memory consists inthe preservation of images imprinted in the mind from previousexperiences, while imagination consists in constructing images thatlack a duplicate in experience.

Reid offers two criticisms of the ancient theory, as he understandsit. First, the theory falls afoul of one of Reid’s ownmethodological strictures, namely, that a theory must adhere toNewton’sregulae philosophandi, or rules ofphilosophizing (Inquiry, 12). The first rule is to posit nomerely theoretical causes and in Reid’s view the second ruleforbids positing causes insufficient to explain the phenomenon inquestion. According to Reid, there is no observational evidence of theexistence of impressions on the brain—they are merelytheoretical entities (Essays, 281). Furthermore, even if wegranted the otherwise theoretical existence of impressions, suchentities would not be sufficient to explain memory. We might establisha correlation between impressions and memories, but it would remain atbest just that: a correlation, not a causal explanation. Havinglearned Hume’s lessons about causation, Reid denies anynecessary connections between impressions and memories sufficient toregard the former as a cause of the latter. Reid also considerswhether resemblance could ground such a causal explanation, but,having learned Berkeley’s lessons about resemblance, he deniesthat any mental states can resemble material states such asimpressions on the brain. Reid’s second criticism is that evenif we were to grant that impressions remain after the objects thatimpressed upon the senses are gone, this would entail that we shouldcontinue to perceive objects rather than remember them, since on theancient theory, impressions are the immediate causes and objects ofperception (Essays, 282).

Though Reid identifies his target as having ancient origins, hisprimary concern is with what he regards as its modern equivalent. Thismodern theory was introduced by Locke and, according to Reid, extendedto its inevitable idealist and skeptical conclusions by Berkeley andHume. Reid excerpts passages from Locke’sEssay ConcerningHuman Understanding to illustrate the misleading metaphors Lockeinherits from the ancient theory—metaphors of the mind as astorehouse and of ideas and impressions as pictures.

The other way of Retention is the Power to revive again in our MindsthoseIdeas, which after imprinting have disappeared, or havebeen as it were laid aside out of sight…This isMemory, which is as it were the Store-house of ourIdeas…But ourIdeas being nothing but actualPerceptions in the Mind, which cease to be any thing, when there is noperception of them, thislaying up of ourIdeas inthe Repository of the Memory, signifies no more but this, that theMind has a Power, in many cases, to revive Perceptions, which it oncehad, with this additional Perception annexed to them, that it has hadthem before. And in this Sense it is, that ourIdeas are saidto be in our Memories, when indeed, they are actually no where, butonly there is an ability in the Mind, when it will, to revive themagain; and as it were paint them anew on it self, though some withmore, some with less difficulty; some more lively, and others moreobscurely (Locke,Essay, Book II.x.1–2).

As this passage illustrates, Locke himself acknowledges that thenotion that the mind is a kind of repository or storehouse ismetaphorical. According to Locke’s own theory, ideas andimpressions cannot be stored. Locke is committed to the thesis thatideas are momentary and non-continuous and to the thesis that theidentity of ideas over time requires continuous existence. These twotheses jointly entail that numerically identical ideas cannot bestored over time. Nevertheless, Reid criticizes Locke for being unableto extricate himself from metaphor when Locke claims that in memory,“the mind, as it were, paints ideas anew on it self.” Onwhat model does the mind paint the idea anew? In order to use aprevious idea as its model, the mind must remember it. But then theability to paint ideas anew upon itself presupposes rather thanexplains memory.

Locke offers a non-metaphorical account of memory when he claims thatmemory consists of two perceptions: a present perception and a beliefabout that present perception, namely that one has enjoyed theperception before. Because Locke is committed to the thesis thatnumerically identical ideas cannot be stored over time, the beliefmust be the belief that one has previously enjoyed a perceptionqualitatively similar to the present perception, rather thannumerically identical with it. Reid criticizes this account ascircular, once more. A first-personal belief that one’s presentperception is qualitatively similar to a perception one had in thepast requires remembering having had that previous perception andrecalling its quality and character. As before, Locke’s accountpresupposes rather than explains the phenomenon of memory(Essays, 285).

Reid criticizes Hume’s account of memory for duplicatingLocke’s mistakes. He quotes from Hume’sTreatise ofHuman Nature:

We find by experience, that when any impression has been present withthe mind, it again makes its appearance there as an idea; and this itmay do after two different ways: Either when in its new appearance itretains a considerable degree of its first vivacity, and is somewhatintermediate betwixt an impression and an idea; or when it entirelyloses that vivacity, and is a perfect idea. The faculty by which werepeat our impressions in the first manner, is call’d theMEMORY, and the other the IMAGINATION (Hume,Treatise,1.1.3.1).

Like Locke, Hume holds that ideas have no continued existence. And so,Reid argues, Hume cannot claim that a numerically identical idea canreappear. In addition, Hume’s account faces the same circularityobjection as Locke’s. Hume accounts for memory by appealing toan idea that is qualitatively similar to, but less forceful andvivacious than a previous idea. But the ability to judge qualitativesimilarity and degrees of force and vivacity between present ideas andpast impressions presupposes memory.

Reid provides additional criticisms of Hume’s account of memory.First, Reid interprets Hume’s account of memory as committinghim to the position that we have the power to repeat ideas (thoughnotice that Hume does not commit to this in the quoted passage). Reidargues that this position is inconsistent with Hume’s claim thatimpressions are the efficient causes of ideas. Reid’s secondcriticism is more insightful; he argues that differences in degrees offorce and vivacity are insufficient to sustain the distinctionsbetween perception, memory and imagination. Reid interprets Hume asholding that these three faculties do not differ in kind, but ratherin the degree of force and vivacity of the ideas that are theirobjects. Ideas with the greatest degree of force and vivacity areperceptions, those with a lesser degree are memories, and those withthe least degree of force and vivacity are imaginings. Reid criticizesthis taxonomy on phenomenological grounds. Some perceptions are lessforceful and lively than some memories, as when lost in reminiscence,and some memories are less forceful and lively than imaginings, aswhen lost in reverie. Furthermore, increasing the degree of force andvivacity does not transform a memory or an imagining into aperception. Reid compares striking one’s head against the wallto lightly touching it to the wall. The latter has much less force andvivacity than the former, yet lightly touching one’s head to thewall is neither a memory nor an imagining (Essays, 289).

Reid grants that perceptions, memories and imaginings often differ indegree of force and vivacity, but, he argues, this difference isinsufficient to account for the special quality of presentnessrepresented in perceptions, the special quality of pastnessrepresented in memories, and the special quality of atemporalityrepresented in imaginings (Inquiry, 197). While memories maybe faint, or weak, these features are not necessary to these statesbeing memories, and so cannot be used to individuate them. Inaddition, a present idea—whatever its degree of force andvivacity—cannot ground judgments about events in the pastbecause present ideas represent events as present.

For according to that theory, the immediate object of memory, as wellas every other operation of the understanding, is an idea present tothe mind. And, from the present existence of this idea of memory I amled to infer, by reasoning, that six months ago or six years ago,there did exist an object similar to this one…But what is therein the idea that can lead me to this conclusion? What mark does itbear of the date of its archetype? (Essays, 476)

Present ideas contain no information, qualitatively orrepresentationally, that could serve as the basis of judgments aboutpast events. As a result, no reflection on present ideas and theirquality or character is sufficient for a representation of events inthe past, as past.

2. A Direct Realist Theory of Memory

Contemporary philosophers and cognitive scientists recognize thatmemory is a diverse phenomenon and they draw some useful distinctionsamong varieties of memory.^[2] For example, Endel Tulving distinguishes between episodic memory,semantic memory and procedural memory. Remembering how to ride a bikeis an example of procedural memory. Remembering that Napoleon wasdefeated at Waterloo is an example of a semantic memory. Rememberingone’s tenth birthday party is an example of an episodicmemory.

The distinction most relevant to the issues Reid, Locke and Hume raisefor memory and personal identity is between semantic and episodicmemory. Henri Bergson and Bertrand Russell developed a similardistinction, and Russell’s distinction between factual andpersonal memory accords with that between semantic and episodicmemory. Semantic memories are properly reported using a factivecomplement—a that-clause—after the verbs‘remember’ or ‘recall’, as in ‘Janeremembers that Napoleon was defeated at Waterloo’. Inparticular, a semantic memorycannot be reported using theform ‘S remembers/recalls [x]f-ing’, as in ‘Jane recalls her tenth birthdayparty,’ or ‘John remembers falling off his bike.’Only episodic memories may be properly reported using this form. Noone today can properly report ‘I remember Napoleon beingdefeated at Waterloo,’ though many may properly report ‘Irememberthat Napoleon was defeated at Waterloo.’ Onthe other hand, an episodic memorycan be reported using thesame form by which semantic memories are reported because episodicmemories may ground semantic memories under certain circumstances. Itis legitimate to state both ‘I recall my tenth birthdayparty,’ in reporting an episodic memory of that event and tostate ‘I remember that I had a tenth birthday party’, inreporting a semantic memory, whose justification would appeal to theprevious episodic memory.

Episodic memories are further distinguished from semantic memories bythe Previous Awareness Condition on episodic memory. The PreviousAwareness Condition has been developed and examined by SydneyShoemaker (1970), among others. Put simply, one has an episodic memoryof an event only if one was agent or witness to the event remembered.The Previous Awareness Condition is a necessary but insufficientcondition on episodic memory. If one has an experience as of beinglost in a store as a child, but one was not in fact lost in a store asa child, such an experience is not an episodic memory. On the otherhand, each of us has been agent or witness to many events of which wehave no episodic memory. For example, one may not remember one’sthird birthday party and so lack an episodic memory of an event towhich one was surely witness. Reid characterizes memory as exhibitingthe Previous Awareness Condition. He holds that reports of episodicmemory are true only if the person reporting satisfies the condition,and that experiences that otherwiseappear to be episodicmemories, but which fail the condition, are not episodic memories(Essays, 264).

Reid is most interested in episodic memory. Though Reid does not usethe contemporary terminology, his theory draws upon both thedistinction between episodic and semantic memory and the PreviousAwareness Condition on episodic memory. As he puts the matter:

Things remembered must be things formerly perceived or known. Iremember the transit of Venus over the sun in the year 1769. I musttherefore have perceived it at the time it happened, otherwise I couldnot now remember it. Our first acquaintance with any object of thoughtcannot be by remembrance. Memory can only produce a continuance orrenewal of a former acquaintance with the things remembered(Essays, 255).

Though Reid uses the term ‘acquaintance,’ the thingsretained through memory are things previously perceived orexperienced. The term ‘acquaintance’ has acquired atechnical sense that it did not have in Reid’s day, so it isbetter to see Reid as holding that memory preserves contact withevents previouslyapprehended through perception and therebyknown by acquaintance. Acquaintance presupposes apprehension, andprior episodes of apprehension are necessary for retainedacquaintance.

According to Reid, episodic memory is not a current apprehension of apast event, nor is it a current apprehension of a past experience.These theoretical options were ruled out by Reid’s criticism ofLocke and Hume. Rather, according to Reid, memory is an act thatpreserves a past apprehension. As we will see below, memory preservespast apprehension by conceiving of an event previously apprehended andbelieving, of this event, that it happened to me.

Reid does not count what we term ‘semantic memories’ asmemories in the proper sense. He discounts them not because they failto meet the Previous Awareness Condition, but because he holds thatsemantic memories are better classified as beliefs or knowledge ratherthan memories. For example, he would hold that a person today whoreports rememberingthat Napoleon was defeated at Waterlooexpresses a belief or knowledge rather than a memory. He holds thisbecause he requires a distinction between two sorts of beliefs thatwould otherwise be obscured by the fact that each sort can beexpressed in the form of a semantic memory report. The distinction isbetween beliefs that play a role in preserving past apprehension (andwhich areconstituents of episodic memory), and those that donot play a role in preserving past apprehension (and which are not,strictly speaking, memories). For example, Jane believes that shedined with a friend last night. Jane has an episodic memory of thisevent, and according to Reid, her belief ‘that I dined with afriend last night,’ plays a role in preserving Jane’s pastapprehension of dining with her friend. On the other hand,Jane’s belief that she had a third birthday party does not playa role in preserving her past apprehension of her third birthdayparty; she has no episodic memory of her third birthday party. Thedifference between these two sorts of belief is obscured by the factthat each may be expressed by using the factive compliment:‘Jane remembersthat she dined with a friend lastnight,’ and ‘Jane remembersthat she had a thirdbirthday party.’

According to Reid, a memory consists in a conception of a past eventand a belief about that past event, that it happened to the person whois represented in that memory as agent or witness (Essays,228, 232, 254, 257). This conception-belief structure mirrorsReid’s accounts of perception and consciousness, each of whichalso consist in a conception and belief. Folescu (2018a) examineswhether memorial conception differs from or is the same as the kind ofconception ingredient in perception, consciousness, and otherintentional mental states. The belief that is a constituent of memory,on Reid’s view, is a belief of some past event, that ithappened. In particular, it is a belief that it happened to me, wherethe pronoun is indexed to the person who is represented in the memoryas agent or witness to the event (Essays, 255, 262). Thebelief isabout orof the event because the otherconstituent of memory—the conception—supplies the event,which is the object of the belief. On Reid’s view, the objectsof memory are the events presented in past apprehensions. Memorypreserves past apprehensions by relating us to the events originallypresented in perception—memory preserves past apprehensionthrough conception and belief. In particular, the objects of memoryare not the past apprehensions themselves but that which is presentedin the past apprehensions, namely, the original event(Inquiry, 28). Folescu (2018b) examines a tension inReid’s accounts of memory and perception. According to Reid, weremember events that were apprehended in the past by perception. ButReid insists that perception is confined to the present. Becauseperception is confined to the present, we cannot perceive events,which have a duration. How, then, can we remember what we cannot haveperceived?

Reid holds that memory is not a current apprehension of an eventalready presented in a past apprehension. In other words, we do notremember events byre-apprehending them. Rather, the pastapprehension is itself preserved by the act of remembering the eventapprehended. Memory is an act of preservation through conception andbelief. Such preservation does not itself constitute anadditional apprehension over and above the apprehensionpreserved. Indeed, according to Reid, it is impossible to currentlyapprehend any events in the past; apprehension is confined toperceiving present objects or being conscious of present mentaloperations (Essays, 23, 253). Reid does not deny that memoryis itself a current mental state, nor does he deny that memorypresupposes a past apprehension. He denies only that memory is acurrent apprehension, and that the object of a memory is a pastapprehension (Essays, 253). Memory preserves pastapprehension by conceiving of an event previously apprehended andbelieving, of this event, that it happened to me.

Reid holds that memory, like perception, is immediate. Neither theconception nor the belief that are the ingredients of memory areformed on the basis of reasoning or testimony. Memory is an originalfaculty of our constitution governed by what Reid calls “thefirst principles of contingent truths.” In the case of memory,the governing principle is that “those things did really happenwhich I distinctly remember” (Essays, 474). OnReid’s view, a normally functioning human does not and need notinfer to a past event in episodic memory. In order to infer to a pastevent, one must have some prior, non-inferential relation to the eventif it is to be a memory rather than a belief or knowledge. But thenthis prior, non-inferential relation would be an episodic memory. Inaddition, if episodic memory involved an inference to the effect thatthe event happened to me, the inference would be otiose because, asReid claims, such a belief is already an immediate, non-inferentialcomponent of episodic memory. In principle, one could infer from theconception and belief that are ingredients in memory to a furtherbelief that the event happened. But if such a belief plays a role inpreserving past apprehension then it is superfluous—such abelief, subject to the Previous Awareness Condition, is alreadyembedded in episodic memory. If the belief does not play a role inpreserving past apprehension then it is a semantic memory, which,according to Reid, is among the species of belief or knowledge rathermemory.

The distinction between beliefs that are ingredients in episodicmemories and beliefs that are based on, but not ingredients in,episodic memories allows Reid to account for cases in which a memorialexperience continues to represent an event as having happened, evenwhen the person who seems to remember the event has what she regardsas an overriding reason to believe that the event did not occur. Thebelief that is an ingredient in the experience represents the event ashaving happened to the person who seems to remember it. Further, thebelief will continue to represent the event as having happened to theperson, even under conditions in which she forms a separate belief,not embedded in the memorial experience, to the effect that it did nothappen to her.

The distinction also allows Reid to satisfy a constraint on anyadequate theory of memory; namely, that it explain why memoryrepresents events as having the special quality of being in the past.If belief were not an ingredient in episodic memory, then though wemightbelieve that the events we remember are in the past,memory could not represent events as past. If belief were notan ingredient in memory, then memory alone would relate us to an eventpreviously apprehended. But the apprehension preserved is anapprehension of an event that was, at that time, represented in thatapprehension as present. The pastness of the event apprehended is notpart of the content of the past apprehension. But because a beliefthat the event happened to me is embedded in the memory itself, memoryrepresents not merely past events, but past events as having occurred.In other words, the belief that is partly constitutive of episodicmemory is tensed. For an alternative view on which the conception thatis partly constitutive of memory is tensed, see Thorpe 2021).

One might wonder whether Reid’s account of memory is subject tothe same criticisms he levels against Locke and Hume. Does Reid appealto the storehouse metaphor when he claims that memory is preservedpast apprehension? Reid criticizes Locke and Hume for begging thequestion. Yet by holding that memory is in part constituted by abelief, does Reid not also assume the very phenomenon to be explained?Reid can avoid the criticisms to which the theory of ideas isvulnerable by insisting that memory is not a current apprehension, butrather a preserved past apprehension. His theory of memory is a directrealist theory because, according to Reid, memory is not directedtowards any present perceptions, ideas, or impressions—stored orotherwise. Neither is memory directed towards any past perceptions,ideas, or impressions—stored or otherwise. Memory is directedtowards the events presented in past apprehensions. Becauseapprehensions, perceptions, ideas, and impressions are never theobjects of memory, they do not need to be stored for use by memory.Likewise, the belief that is an ingredient in memory is not about anypresent or past apprehensions. If it were, Reid’s theory wouldbe subject to the same circularity objection he presses against Lockeand Hume.

On Reid’s theory of memory, an apprehension establishes a directrelation to an event, which relation is preserved in memory by theacts of conceiving the event and believing of the event conceived thatit happened to the person who remembers. It is a direct realist theoryof memory because it departs from the model on which memory is acurrent apprehension of a past event or a current apprehension of apast apprehension. On the direct realist view, memory preserves pastapprehension of an event through conception and belief. WhileCopenhaver (2006, 2017, and Copenhaver & Rysiew forthcoming)interprets Reid’s direct realism along intentionalist /representationalist lines, he could be interpreted as not only adirect realist but also a naive realist if one were to interpret himalong relationalist / disjunctivist lines. Either way,Reid’s theory captures how memory, like perception, representsthe world, rather than our experiences of the world, which is whatmakes him direct realist.

3. Objecting to Locke on Personal Identity

Reid, Locke and others are interested in the notion of episodic memorynot only for its own sake, but also because of its conceptualconnection to the notion of personal identity. If Joe remembers,episodically, winning the World Series, then Joe must have existed atthe time of his winning the World Series. This is why the PreviousAwareness Condition characterizes episodic but not semantic memory.Unlike Joe’s memory that Napoleon was defeated at Waterloo, hismemory of winning the World Series logically entails Joe’sexistence at the time of the event remembered. In other words,episodic memory is logically sufficient for personal identity: ifS remembers at timet_n(episodically) an event at timet₁, thenS existed at timet₁. In addition, memoryreports are often taken to beprima facie evidence forstatements about the past history of the person reporting.

Reid’s main criticism of Locke’s theory of personalidentity is that Locke moves from these truisms concerning theconceptual and evidential relations among the notions of memory andpersonal identity to a hypothesis concerning the metaphysicalrelations among them (Essays, 277). In this, Reid followsButler’s influential dissertation “Of PersonalIdentity,” appended toThe Analogy of Religion in1736.

Reid interprets Locke as holding what is now called the Memory Theoryof personal identity (Essays, 277). On this theory, personalidentityconsists in memory; sameness of episodic memory ismetaphysically necessary and sufficient for sameness of persons. Inother words, on the Memory Theory, whatmakes a personidentical with herself over time is her remembering or being able toremember the events to which she was witness or agent. If she cannotepisodically remember an event, then she is not identical with any ofthe persons who was witness or agent to the event. In such a case, shewould bear the same relation to that event as any other person forwhom a memory of the event could rise at best to the level of asemantic memory. If she can episodically remember an event, then herrecollection or ability to recall that event makes her identical withthe person represented in that memory as agent or witness to theevent.

But there is a secondary, more subtle line of disagreement betweenReid and Locke. Much of Locke’s chapterIdentity andDiversity is dedicated to establishing that the self is not asubstance, material or immaterial. By contrast, Reid holds that theself is a simple, unanalyzable immaterial substance with activepowers. Reid argues that Locke cannot sustain both the thesis that theself is not a substance and the thesis that self remains identicalover time. While Reid’s criticisms of the Memory Theory are morewell known, his criticism of Locke’s insistence that the self isnot a substance reveals two very different accounts of the metaphysicsof identity. While Locke argues that the identity conditions fordifferent kinds of things differ, so that the conditions under which amass of matter, and an animal, and a person are not the same, Reidholds that identity is confined solely to substances that have acontinued, uninterrupted existence and which do not have parts. Inother words, according to Reid, strictly speaking the only realidentity is personal identity (Essays, 266–267).“The identity…we ascribe to bodies, whether natural orartificial, is not perfect identity; it is rather something which, forthe conveniency of speech, we call identity” (Essays,266).

Reid begins his interpretation and criticism of Locke’s theoryby noting that Locke defines the term ‘person’ as meaning“a thinking intelligent Being, that has reason andreflection…” (LockeEssay, Book II.xxvii.9).Reid is friendly to this characterization of the self. But, Reidnotes, Locke appears to equivocate between the notion of a person as a‘thinking Being,’ and the notion of a person as that whichis preserved through consciousness and memory. Reid paraphrases apassage from Locke’sEssay Concerning HumanUnderstanding:

Mr LOCKE tells us however, “that personal identity, that is, thesameness of a rational being, consists in consciousness alone, as, asfar as this consciousness can be extended backwards to any past actionor thought, so far reaches the identity of that person. So thatwhatever hath the consciousness of present and past actions, is thesame person to whom they belong” (Essays275–276).

The passage in Locke differs from Reid’s paraphrase:

…personalIdentity, i.e. the sameness of arational Being: And as far as this consciousness can be extendedbackwards to any past Action or Thought, so far reaches the Identityof thatPerson; it is the sameself now it was then;and ‘tis by the sameself with this present one thatnow reflects on it, that that Action was done (Locke,Essay,Book II.xxvii.9).

Reid’s first criticism rests on his interpreting Locke’sdefinition as committing him to the position that a person is asubject of thought, which Reid regards as implying that a person is athinking substance. At the same time, Locke appears to be committed toan analysis of personal identity in terms of memory, or, as Lockewould put it, consciousness of the past. Reid notes that Locke isaware of some of the consequences of the Memory Theory: if sameness ofconsciousness or memory is necessary and sufficient for sameness ofperson, then it is possible for there to be sameness of person withoutsameness of thinking Being. In other words, it is logically andmetaphysically possible for a person to be “transferred from oneintelligent being to another,” or for “two or twentyintelligent beings to be the same person” (Essays,276). Locke’s response to these worries, as well as worriesabout periods of interrupted consciousness, as in sleep, highlightsReid’s criticism: “…[I]n all thesecases…doubts are raised whether we are the same thinking thing;i.e. the same substance or no. Which however reasonable, orunreasonable, concerns notpersonal Identity at all. TheQuestion being what makes the samePerson, and not whether itbe the same Identical Substance…” (Locke,Essay,Book II.xxvii.10). Reid’s criticism is not that cases oftransfer or fission are incoherent, though he thinks they are. Rather,his criticism is that the possibility of sameness of person withoutsameness of thinking Being that the Memory Theory allows isinconsistent with Locke’s characterization ofa personas a ‘thinking Being’. Given that Reid thinks that thisinitial characterization is correct, he regards this as areductio of the Memory Theory.

Reid’s second criticism is his most famous and is often referredto as the case of the Brave Officer:

Suppose a brave officer to have been flogged when a boy at school, forrobbing an orchard, to have taken a standard from the enemy in hisfirst campaign, and to have been made a general in advanced life:Suppose also, which must be admitted to be possible, that when he tookthe standard, he was conscious of his having been flogged at school,and that when made a general he was conscious of his taking thestandard, but had absolutely lost the consciousness of his flogging.

These things being supposed, it follows, from Mr LOCKE’sdoctrine, that he who was flogged at school is the same person whotook the standard, and that he who took the standard is the sameperson who was made a general. When it follows, if there be any truthin logic, that the general is the same person with him who was floggedat school. But the general’s consciousness does not reach so farback as his flogging, therefore, according to Mr LOCKE’sdoctrine, he is not the person who was flogged. Therefore the generalis, and at the same time is not the same person as him who was floggedat school (Essays, 276).

According to the Memory Theory, personal identityconsists inmemory; that is, sameness of memory is metaphysically necessary andsufficient for sameness of person. On this account, given thatsameness of memory is sufficient for sameness of person, if a personat timet_n remembers (episodically) anevent that occurred at timet₁ then the person attimet_n is identical with the person whowas witness or agent to the event at timet₁. Ifthe brave officer who has just taken the flag of the enemy remembersbeing beaten at school, then the brave officer is identical with theboy who was beaten. So too, if the general remembers taking theenemy’s flag, then the general is identical with the braveofficer. If the general is identical with the brave officer, and thebrave officer is identical with the boy, then by the transitivity ofidentity, the general is identical with the boy.

However, on this account, given that sameness of memory is a necessarycondition for sameness of person, if a person at timet_n does not remember (episodically) anevent that occurred at timet₁, then the person attimet_n cannot be identical with anyperson who was witness or agent to the event at timet₁. If the general cannot remember being beaten atschool, he cannot be identical with the boy who was beaten. Thus, theMemory Theory is committed to mutually incompatible theses: that theGeneral is identical with the boy and that he is not.

Reid’s third criticism is terminological: he argues that Lockeconfounds consciousness with memory—elsewhere Reid also arguesthat Locke confounds consciousness with reflection (Essays,58). Consciousness and memory are distinct phenomena, according toReid. The former is directed towards present mental acts andoperations, while the latter is directed towards past events to whichone was agent or witness. If consciousness could extend to pastevents, then memory would be redundant (Essays, 277).

According to Reid, memory is neither necessary nor sufficient forpersonal identity, metaphysically speaking, despite the conceptual andevidential relations memory bears to personal identity. It is not anecessary condition because each us has been agent or witness to manyevents that we do not now remember. “I may have other goodevidence of things which befell me, and which I do not remember: Iknow who bare me, and suckled me, but I do not remember theseevents” (Essays, 264). It is not a sufficientcondition, for, as Butler showed, while having an episodic memory ofan event entails that one existed at the time of the event remembered,it is not the recollection or the ability to recall thatmakes one identical with the person who was witness or agentto the event. “It may here be observed…that it is not myremembering any action of mine that makes be to be the person who didit. This remembrance makes me know assuredly that I did it; but Imight have done it, though I did not remember it”(Essays, 265). Reid’s fourth criticism is that whilememory is tied to personal identity conceptually and evidentially,such ties do not entail a metaphysical connection that would licenseanalyzing the latter in terms of the former (Essays,277).

Reid’s final criticism is that the Memory Theory is committed tothe absurdity that identity consists in something that has nocontinued existence (Essays, 278). Reid and Locke agree thatmemory, consciousness, thought, and other mental operations have nocontinued existence. They are fleeting and non-continuous. But theyalso agree that identity, and in particular personal identity,requires a continued existence over time. As Locke puts it, “onething cannot have two beginnings of Existence, nor two things onebeginning” (Locke,Essay, Book II.xxvii.1). But thesecommitments are jointly inconsistent with the thesis that personalidentity consists in memory.

A theory of personal identity is intended to account for how a personremains identical over time. When analyzed in terms of items that arefleeting and non-continuous—ideas, memories,thoughts—identity is reduced to diversity; that is, it iseliminated. By contrast, if one locates personal identity in thatwhich thinks and remembers, and which has a continued, uninterruptedexistence, one purchases personal identity at the cost of admittingthat the self is a substance. Reid captures Locke on the horns of adilemma: either the self is a substance, in which case it remainsidentical over time, or the self is not a substance, in which casethere is no personal identity. Reid holds that this dilemma applieswith equal force against any reductionist account of personal identitythat employs the theory of ideas, for example Hume’s bundletheory of the self (Essays, 473–474).

4. Personal Identity as Simple and Unanalyzable

Those familiar with the contemporary literature on personal identity,with its emphasis on the necessary and sufficient conditions underwhich a person remains identical over time, may wonder: if Reid holdsthat memory is not the criterion of identity, and if Reid’ssubstance dualism rules out bodily identity as a criterion of personalidentity, in whatdoes personal identity consist?Reid’s answer is that identity cannot be accounted for in anyterms other than itself. This is neither quietism nor epistemichumility on Reid’s part. Rather, Reid argues that the nature ofpersonal identity—its simplicity and indivisibility—rulesout any reductive account that appeals to notions other than identityin explaining how a person persists over time.

Reid holds that numerical identity is, strictly speaking, indefinable,but it can be contrasted with other relations, such as diversity,similarity and dissimilarity (Essays, 263). It requires acontinued existence over time—a duration—and requires thatthere be no two beginnings of existence. Because mental states arefleeting and non-continuous they cannot remain identical over time. Amental state may be indistinguishable from a previous mental state,but because mental states do not have a continued existence, no mentalstate at one time can be numerically identical with another at adifferent time. As a result, persons cannot be identified with theirthoughts, actions or feelings (Essays, 264). However,according to Reid, thoughts, actions, feelings and all other mentaloperations are had or performed by a subject that has a continuedexistence and that bears the same relation to all them. The subject isan immaterial substance that thinks, acts and feels. According toReid, this substantial self has no parts—it isindivisible—which contributes to its resistance to reductiveexplanation. Reid appeals to Leibniz’s notion of amonad to describe the indivisibility of this immaterial,substantial self (Essays, 264).

Though memory is not the metaphysical ground of personal identity, itprovides first-personal evidence of it. Reid notes that the evidencewe use to make judgments about our own pasts is different from theevidence we use to make judgments about other people and their pasts(Essays 266). Memory justifies first-personal reports aboutone’s own witnessed past, while judgments of qualitativesimilarity justify third-personal statements about the identities ofother persons. I know that I was present at my wedding because Iremember being there. I know that the man I live with was at mywedding because he looks like the man I married.

First-personal, memorial reports about one’s own past are eithertrue or false: if the memorial experience is a genuine episodicmemory, then it is impossible for it to testify falsely concerningone’s presence at the event remembered. This aspect of episodicmemory reports is often expressed by saying that they are immune toerror through misidentification. If the memorial experience testifiesfalsely concerning one’s presence at the event remembered, thenit cannot be an episodic memory. For example, if I have an experienceas of having been lost in a shopping mall as a child, but I was neverlost, I cannot be said to remember having been lost, strictlyspeaking. The upshot is that first-personal memorial reports, if theyare episodic memory reports, provide certainty concerning one’spresence at the event remembered. Because third-personal judgmentsabout the pasts of other persons are based on judgments of qualitativesimilarity rather than episodic memory, they are never certain; theyare only ever more or less well justified (Essays264–265).

It is important to notice that while Reid uses the term‘evidence,’ when describing the role that memory plays infirst-personal knowledge of one’s own past, memory is notused by persons to justify judgments or beliefs about theirown pasts. In other words, people do not remember events and thenconclude from having remembered them, that it wasthey who were witness to the events. Rather, memory itselfrepresents one’s presence at the event remembered. According toReid, a memory consists in a conception of an event and a belief,about the event conceived, that it happened to me, where the pronounis indexed to the person who is represented in the memory as agent orwitness. In other words, memory consists in part in a judgment thatrepresents one’s presence at the event. Any further judgment,justified by memory, to the effect thatI was the person whowas there would be superfluous—memory already testifies to myhaving been there. This is why Reid calls the evidence of memoryimmediate: first-personal statements about one’s ownpast are memory statements, not statements made on the basis ofmemory.

Reid’s picture is one on which each of us is immediately andjustifiably aware of our own past because each of usremembers having been there. This is the moral of the storyconcerning the logical relationship between the concept of memory andthe concept of personal identity. Memories do notmake me thesame person as the person represented in my memories. Rather, memoriesallow me to know my own past, immediately and directly.

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identity |Locke, John |memory |personal identity |personal identity: and ethics |Reid, Thomas |substance