Questions: Persistence and Change

Question 1

A leaf is green in summer and red in autumn. An endurantist must explain how the same object can appear to have two incompatible intrinsic properties. Which response best characterizes the standard endurantist move?

• A. The summer leaf and autumn leaf are numerically distinct objects — endurantism denies strict identity across change
• B. Relativize property instantiation to times: the leaf has greenness-at-t1 and redness-at-t2, rather than greenness and redness simpliciter
• C. Intrinsic properties are not real; only extrinsic relational properties exist, so no contradiction arises
• D. The incompatibility dissolves once we recognize colors as subjective percepts, not objective properties of objects

Answer: (B)

The standard endurantist response to the problem of temporary intrinsics is to relativize property instantiation to times (or treat temporal properties as disguised relations to times). Instead of the leaf having 'greenness' as a bare intrinsic property, it has 'greenness-at-t1' — a time-indexed property that does not conflict with 'redness-at-t2.' The cost is that properties are no longer purely intrinsic to their bearers; they are relational in a way that Lewis found unsatisfying, which motivates the perdurantist alternative.

Question 2

How does perdurantism dissolve the problem of temporary intrinsics without relativizing properties to times?

• A. By denying that objects have any intrinsic properties at all
• B. By holding that the same four-dimensional object is wholly present at every moment and simply has all its properties at once
• C. By saying the summer leaf and autumn leaf are distinct temporal parts, each bearing its intrinsic properties simpliciter — no time-relativization needed
• D. By treating time as unreal so that apparent change is an illusion requiring no metaphysical explanation

Answer: (C)

Perdurantism says objects are extended through time and have distinct temporal parts (stages). The summer leaf and autumn leaf are different temporal stages of a single four-dimensional entity — each temporal part simply has its intrinsic property (greenness, redness) without qualification, just as different spatial parts of a tree can simultaneously have different colors without contradiction. Lewis endorsed perdurantism precisely because it dissolves the temporary intrinsics problem: no time-relativization of properties is needed, because different temporal parts are the property-bearers.

Question 3

On the perdurantist view, the persistence of an object through time is analogous to its extension through space — just as an object can have different properties in different spatial regions, it can have different properties in different temporal stages.

• T. True
• F. False

Answer: True

Perdurantism explicitly draws this spatial analogy. A tree's top is green and its roots are brown — we find no contradiction because they are distinct spatial parts. Perdurantism extends this logic: the summer leaf and autumn leaf are distinct temporal parts of a four-dimensional entity, each bearing its intrinsic properties without contradiction. Lewis used this spatial analogy directly to argue that temporary intrinsics pose no more problem than 'simultaneous intrinsics' for spatially extended objects.

Question 4

The debate between endurantism and perdurantism is fundamentally about whether objects change at most — endurantists deny real change while perdurantists accept it.

• T. True
• F. False

Answer: False

Both endurantists and perdurantists fully accept that objects undergo change — the leaf really does go from green to red, and this is not an illusion. The debate is entirely about the *metaphysical structure* that makes change possible: does the same wholly-present object bear different properties at different times (endurantism), or do distinct temporal parts bear the different properties (perdurantism)? This is a question about what change *is* at the fundamental level, not whether it occurs.

Question 5

What is the 'problem of temporary intrinsics,' and why does it create a difficulty specifically for endurantism but not perdurantism?

Model answer: The problem of temporary intrinsics (articulated by David Lewis) is this: intrinsic properties seem to belong to their bearers absolutely — if an object is green, it is green full stop, not green-relative-to-something. But if the same object is wholly present at both t1 (when it is green) and t2 (when it is red), it appears to possess both greenness and redness, which are incompatible. Endurantism must handle this by either relativizing property instantiation to times ('greenness-at-t1') or treating temporal properties as relations to times — both of which make intrinsic properties relational in a way that conflicts with their defining character. Perdurantism avoids the problem entirely: the summer and autumn leaf are distinct temporal parts, each bearing its intrinsic property simpliciter, just as distinct spatial parts of an object can bear different intrinsic properties without contradiction.

Stage theory offers a third route: ordinary objects just are instantaneous temporal stages, and 'persistence' is a counterpart relation between stages. Each stage has its intrinsic properties without relativization, but 'the leaf' at different times refers to numerically distinct stages — avoiding both the temporary intrinsics problem and the four-dimensional worm metaphysics of standard perdurantism.