What makes you the same person over time, despite the constant change in your body and mind?
explain and evaluate theories of personal identity, including the body, soul and psychological-continuity criteria
A focused QCE Unit 4 answer on personal identity. Covers the persistence question, the body and soul criteria, Locke's memory or psychological-continuity theory, the duplication and circularity objections, Reid's brave officer case, and Parfit's claim that identity is not what matters.
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What this dot point is asking
QCAA wants you to engage the metaphysics of the self: what makes a person at one time the same person as someone at another time, given that body, beliefs and memories all change? You need the persistence question, the main criteria (body, soul, psychological continuity), the classic objections, and the radical conclusion drawn by Derek Parfit. It connects to mind, free will and moral responsibility.
The answer
The persistence question
The question of personal identity over time asks: what makes a person P2 at a later time the same person as P1 at an earlier time? This is not about feeling similar but about numerical identity, being one and the same individual. It matters because responsibility, promises, punishment, anticipation and self-concern all presuppose that the future person is me.
The body and brain criteria
The bodily criterion says you persist as long as the same living body (or at least the same brain) continues. It fits the everyday way we re-identify people. Objection: thought experiments such as brain or body swaps suggest that, if your psychology were transferred to a new body, you would seem to go with the psychology, not the old body. This pushes many toward a psychological criterion.
The soul criterion
A soul criterion says you persist because the same immaterial soul persists, regardless of bodily change. It accompanies substance dualism. Objection (pressed by Locke): we have no way to track souls; if souls could be swapped without any noticeable change, the criterion gives no usable account of identity and detaches it from everything we care about.
Locke and psychological continuity
John Locke, in the Essay concerning Human Understanding (1694), proposed the memory (psychological) criterion: a person at a later time is the same as one earlier if they are connected by consciousness, paradigmatically memory. You are the being whose past experiences you can remember as your own. Strength: it captures why identity matters to us (it tracks the inner life), and it allows the same person to survive bodily change. The view was developed into a psychological-continuity theory: identity consists in overlapping chains of memory, intention, belief and character, even where no single direct memory reaches all the way back.
Objections to the memory criterion
- The circularity objection (Joseph Butler): memory presupposes identity, since to genuinely remember an experience is already to remember it as mine, so memory cannot non-circularly define identity.
- Reid's brave officer: a general remembers, as a young officer, being a boy who was flogged; the elderly general no longer remembers the flogging. By the memory criterion the general both is and is not the same person as the boy, which is contradictory. (The continuity version, using overlapping chains, is designed to answer this.)
- The duplication / fission objection: if your psychology could be copied into two bodies, both would have equal claim to be you, yet you cannot be identical to two distinct people. So psychological continuity cannot be sufficient for identity.
Parfit: identity is not what matters
Derek Parfit, in Reasons and Persons (1984), uses fission cases to argue a striking conclusion: in such cases there is no determinate answer to whether you survive, and that is fine, because identity is not what matters. What matters is psychological continuity and connectedness (Relation R), which can hold to a duplicate. If so, much of our self-concern and even our fear of death may rest on a confusion. Parfit thought this conclusion, though counterintuitive, was liberating.
Try this
Q1. Explain Locke's memory criterion of personal identity. [3 marks]
- Cue. A later person is the same as an earlier one if connected by consciousness, paradigmatically memory of the earlier experiences as one's own.
Q2. Explain Reid's brave officer objection. [3 marks]
- Cue. Overlapping but non-transitive memories make the old general both identical and not identical to the flogged boy, a contradiction.
Q3. State Parfit's conclusion from fission cases. [3 marks]
- Cue. Identity is not what matters; psychological continuity and connectedness are what we actually care about.
Exam-style practice questions
Practice questions written in the style of QCAA exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.
QCAA 20227 marksEvaluate the psychological-continuity theory of personal identity, with reference to at least one objection.Show worked answer →
A 7 mark response explains the theory, its appeal, and an objection.
The theory. Developing Locke's memory criterion, the psychological-continuity theory holds that a later person is the same as an earlier one if connected by overlapping chains of memory, intention, belief and character, even where no single memory reaches all the way back.
Strength. It captures why identity matters to us (it tracks the inner life), allows a person to survive bodily change, and answers Reid's brave officer by using overlapping chains rather than direct memory.
Objection (the duplication or fission case). If your psychology could be copied into two bodies, continuity would hold with both, yet you cannot be numerically identical to two distinct people. So psychological continuity cannot be sufficient for identity. Parfit draws the radical conclusion that identity is not what matters; continuity and connectedness are.
Verdict. The theory best captures what we care about, but fission shows it cannot constitute strict numerical identity, supporting Parfit's reframing.
Markers reward the theory, a genuine strength, the fission objection, and a justified conclusion.
QCAA 20235 marksExplain Butler's circularity objection to Locke's memory criterion and assess whether the psychological-continuity version escapes it.Show worked answer →
A 5 mark response states the objection and judges the continuity reply.
Butler's objection. To genuinely remember an experience is already to remember it as mine, so memory presupposes the very identity it is meant to define. Defining identity by memory is therefore circular.
The continuity reply. The continuity theory replaces direct memory with overlapping chains of psychological connections (quasi-memory, intention, character) and can use a notion of quasi-memory that does not build in identity, aiming to break the circle.
Assessment. This blunts the circularity charge if quasi-memory can be specified without presupposing identity, but critics argue any genuinely first-personal recollection still smuggles in ownership, so the objection is weakened rather than fully dissolved.
Markers reward an accurate statement of circularity and a reasoned judgement on the continuity response.