The main topic of Locke’s chapter is whether personal identity depends on the identity of a material or immaterial substance. Most of his discussion concerns immaterial substances.
Last time, we covered these topics: identity in general and the distinction between person and man.
Today we get to the main topic: whether personal identity depends on the identity of substances or not.
This is where he argues that memory is necessary and sufficient for personal identity over time.
§13. First question: is having the same immaterial substance a necessary condition of being the same person? (The “first part of the Question” is a reference to the first part of the first sentence of §12.) Locke’s answer comes in the last two sentences: no. He takes a long time getting there. The bulk of the paragraph expresses uncertainty about whether it is genuinely possible to transfer consciousness from one immaterial substance to the other. Assuming that it is possible to transfer consciousness from one substance to another, Locke expresses faith that God would not transfer the consciousness of one person’s crimes to another person. He finally returns to the question in the last two sentences. There, he says that if consciousness were transferred from one thinking substance to another, the person would be transferred too. That is the answer: having the same immaterial substance is not a necessary condition of being the same person.
§14. Second question: is having the same immaterial substance a sufficient condition of being the same person? (The “second part of the Question” is a reference to the second part of the first sentence of §12.) Locke says no. He argues for this answer with an example of a “very rational man” who believes he has Socrates’s soul but cannot remember having been Socrates. Locke thinks it is obvious that the very rational man is not the same person as Socrates even if he has Socrates’s soul. So having Socrates’s soul is not a sufficient condition of being the same person as Socrates.
§15. Claim: person and man are distinct. One man (that is, one living human animal) can have two different persons and one person can occupy two different men. So being the same man is neither a sufficient nor a necessary condition of being the same person. Locke illustrates the point with an example of a prince switching bodies with a cobbler.
§16. Claim: being conscious of a past person’s thoughts and experiences is a sufficient condition of being identical with that past person. Locke illustrates the point with an example of remembering having seen Noah’s ark. If Locke can remember this, then he would be identical with the person who originally saw Noah’s ark.
Remembering a past person’s thoughts and experiences is sufficient for being identical with that past person; that is all that has to be the case in order to establish that the two people at different times are the same person. If that is so, then having the same substance is not a necessary condition of being identical with a past person. If all that is needed are memories, then there is no need for identical substances.
Note: §§14–15 implicitly show that being conscious of a past person’s thoughts and experiences is a necessary condition of being the same person over time. That is why the ‘very rational man’ is not the same person as Socrates and why the person who wakes up in the cobbler’s body is not the same person as the one who went to bed in the cobbler’s body (before the prince “switched” in).
§17. Claim: consciousness is sufficient for personal identity. Suppose my little finger were cut off. Suppose also that my consciousness goes with the little finger: I feel sensations through the little finger but I do not feel anything from the rest of what used to by my body. Then I (the person) would be in the little finger and not the rest of my (former) body.
This is directed at the view that a person is identical with an immaterial soul with the following property: it is wholly present throughout the body. See the note on Aquinas and Hobbes at the bottom of this document.
§18. Claim: consciousness is necessary for personal identity. Again, suppose my little finger is cut off and that my consciousness goes with the little finger, meaning that I can feel sensations through the finger but not from the rest of the body. If there is no conscious connection between the body and the finger, then the person who is in the finger cannot be identical with the person in the body.
§19. Locke supports his view by arguing it is consistent with the rules of justice. If waking Socrates cannot remember what sleeping Socrates did, it would be unjust to punish waking Socrates for the actions of sleeping Socrates. Waking Socrates and sleeping Socrates are two different people because neither can remember the other’s thoughts and experiences. This is so even though they inhabit one body.
§20. Objection: what if I forget something from last year? Does that mean I did not exist last year? Locke’s answer is that the man that I am now might have existed during the time I cannot remember, but the person that I am now did not.
As evidence to support his point, he notes that the law does not punish Sober Man for what Mad (Drunk) Man did. This is the same point as the one made in the previous section. (See also §22, which discusses an objection to this point.)
§21. Objection: it is hard to believe that there could be more than one person (Waking Socrates and Sleeping Socrates) in one living body (Socrates, the man). Locke concedes that this sounds odd, but, he maintains, his system is less paradoxical than the alternatives.
§22. Objection: contrary to what Locke said in §20, we do punish sober people for what they did when they were drunk, even if they cannot remember having done it. Locke’s answer is that human justice is imperfect. We do not know if the sober person really does not remember and so we guess. We will sometimes be wrong, but God will get it right.
§23. Locke extends the example of waking and sleeping Socrates from the body to the soul. Day-man and Night-man are two people with “incommunicable consciousnesses” inhabiting one body, much like waking and sleeping Socrates (§19). The earlier example is about two people in one man (one living, material body). In this paragraph, Locke extends the point to immaterial souls. He says Day-man and Night-man would be two different people even if their consciousnesses were “annexed” to a single immaterial substance (or spirit).
§24. Locke begins repeating himself: this will continue through the end. He begins this section by reiterating two points. First, I count body parts as parts of my body only if I can be consciously aware of them (e.g. my toes can feel cold to me but I cannot feel anything from your toes). Second, I identify with past people only if I can consciously remember having had their thoughts and experiences. Locke notes that both points leave out substances: I do not feel or remember anything about a material or immaterial substance. So substances, whether material or immaterial, are irrelevant to questions of personal identity.
§25. Locke concedes that it is likely that consciousness depends on an immaterial substance rather than a material brain. However, Locke argues, it does not follow that personal identity consists in the identity of an immaterial substance. In making his case, he repeats the points from the previous paragraph (which, in turn, repeat the arguments given earlier in the chapter). I do not think that a body part that I cannot feel is part of me or my body, so why would I think that the past thoughts and experiences of an immaterial substance that I cannot remember are part of me or my mind?
§26. Locke reiterates his points about justice and responsibility. Earlier, Locke said that the term “person” stands for a thinking thing, etc. (see §9). Now he adds that “person” is a “forensick term,” meaning that persons are morally and legally responsible for their actions. Locke claims that his theory applies here as well. He thinks people are responsible only for what they can remember having done. That is because remembering having done an action is a necessary condition of being the person who did it. Punishing people for things they cannot remember doing would be like punishing them for the actions of completely different people.
§27. Locke concedes that his theory sounds strange. But, he notes, none of us really understand how we are capable of having conscious thought. For all we know, there are multiple immaterial substances moving in out and out of our minds much as our bodies gain and lose bits of physical matter. What we know is our conscious experience. So, as strange as it sounds to say so, that is what we refer to and care about when we think about ourselves.
§28. Locke repeats his initial remarks about identity (see §1–3).
§29. Application of those points to the idea of man. (I do not know what he was trying to accomplish here.)
Locke’s example of consciousness going “along with” the little finger (§17) is obscure to us. But it actually tells us quite a lot about who he thought his opponents were. That is because the example of the little finger would have been a familiar to his readers.
St. Thomas Aquinas (1225–1274) held that a person is identical with an immaterial soul. One piece of matter cannot be entirely in one place and entirely in a different place at the same time: it is either entirely in one place, entirely in the other place, or partly in the one place and partly in the other. An immaterial soul would not have the properties of matter and so, Aquinas argued, it could be wholly in every part of the body. Thus it could be wholly in the little finger and wholly in the big toe and wholly in the right earlobe, and wholly in the spleen, and so on.
Aquinas’s explanation of how this is possible involves distinguishing between three different ways of using the term “whole” (or “totality”). The one that is relevant to the soul concerns a thing’s essence. Here is an illustration of what he means by that. Take a completely white eggshell. The eggshell has different parts, but each of them is the same color; no part is more white than any other part. For Aquinas, that means the essence of the color white is wholly in each part of the eggshell. By analogy, the essence of a person is wholly in each part of the body. Your lungs are no more, and no less, part of you than your feet are.
if the soul were united to the body merely as its motor, we might say that it is not in each part of the body, but only in one part through which it would move the others. But since the soul is united to the body as its form, it must necessarily be in the whole body, and in each part thereof. For it is … the substantial form of the body. Now the substantial form perfects not only the whole, but each part of the whole. For since a whole consists of parts, a form of the whole which does not give existence to each of the parts of the body, is a form consisting in composition and order, such as the form of a house; and such a form is accidental. But the soul is a substantial form; and therefore it must be the form and the act, not only of the whole, but also of each part. Therefore, on the withdrawal of the soul, as we do not speak of an animal or a man unless equivocally, as we speak of a painted animal or a stone animal; so is it with the hand, the eye, the flesh and bones …
That it is entire in each part thereof, may be concluded from this, … a whole is that which is divided into parts, [and] there are three kinds of totality, corresponding to three kinds of division. There is a whole which is divided into parts of quantity, as a whole line, or a whole body. There is also a whole which is divided into logical and essential parts: as a thing defined is divided into the parts of a definition …. There is … a third kind of whole which is potential, divided into virtual parts. …
Therefore if it be asked whether the whole whiteness is in the whole surface and in each part thereof, it is necessary to distinguish. If we mean quantitative totality … then the whole whiteness is not in each part of the surface. The same is to be said of totality of power: since the whiteness which is in the whole surface moves the sight more than the whiteness which is in a small part …. But if we mean totality of species and essence, then the whole whiteness is in each part of a surface.
Since, however, the soul has not quantitative totality … the whole soul is in each part of the body, by totality of perfection and of essence, but not by totality of power. For it is not in each part of the body, with regard to each of its powers; but with regard to sight, it is in the eye; and with regard to hearing, it is in the ear; and so forth.2
Thomas Hobbes (1588–1679) was a materialist, meaning that he believed everything that exists is made of matter. Obviously enough, then, he did not believe in immaterial souls. He dismissed Aquinas’s suggestion by invoking the dreaded little finger.
For the circumscription of a thing, is nothing else but the determination, or defining of its place; and so both the terms of the distinction are the same. And in particular, of the essence of a man, which (they say) is his soul, they affirm it, to be all of it in his little finger, and all of it in every other part (how small soever) of his body; and yet no more soul in the whole body, than in any one of those parts. Can any man think that God is served with such absurdities? And yet all this is necessary to believe, to those that will believe the existence of an incorporeal soul, separated from the body.3
Locke, like Hobbes, rejected Aquinas’s view. However, he did not dismiss it as ridiculous. He just insisted that the person would go along with whatever sustains consciousness. If that is the little finger, then the person would go along with the little finger, even if the immaterial substance of the soul remains wholly present in the rest of the body. Locke also rejected Hobbes’s suggestion that a person is just a living material body on similar grounds. If consciousness could be transferred to another body, as in the case of the Prince switching bodies with the Cobbler, then the person would go to the new body along with its consciousness rather than staying with the old body.