A student says: 'B-theory must be wrong because I obviously experience time as passing — the present feels vivid and real in a way the future doesn't.' How would a committed B-theorist most likely respond?
AConcede that subjective experience is the strongest evidence for A-theory and that B-theory cannot account for it
BArgue that the experience of temporal passage is explained by our asymmetric cognitive access to past (memory), present (perception), and future (anticipation), which produces a perspectival sense of flow without requiring any objective, mind-independent 'now'
CDeny that the felt sense of temporal passage is a genuine experience, claiming it is a neurological artifact
DAccept that the present is objectively privileged but maintain that B-theory is still useful as a scientific model
B-theorists do not deny that we experience time as passing — they offer an explanation for why we do. The asymmetry of our cognitive access (memories of the past, perceptions of the present, anticipations of the future) creates a phenomenological sense of flow and nowness without requiring that the present be metaphysically privileged. The B-theorist analogy is to spatial experience: 'here' also feels uniquely vivid and present, but no one concludes that one spatial location is metaphysically special. Option A mistakes phenomenological evidence for metaphysical proof; B-theorists argue the phenomenology is compatible with their view.
Question 2 Multiple Choice
Special relativity is often cited as evidence for B-theory over A-theory. What is the core of this argument?
ASpecial relativity shows that time travel is physically possible, which is only consistent with a B-series block universe
BSpecial relativity shows that time can be exchanged for space in the Lorentz transformation, meaning they are the same thing and neither flows
CIn special relativity, simultaneity is relative to reference frames — there is no absolute, observer-independent 'now' across space — making an objective present metaphysically hard to sustain
DSpecial relativity proves that time is an illusion created by observers moving at different velocities
The key argument is about simultaneity. If 'the present' is a real, objective feature of the universe, all observers should agree on which events are happening 'now.' But special relativity shows that two events that are simultaneous in one reference frame are not simultaneous in another. There is no privileged reference frame, and hence no privileged 'now' that all observers share. A-theorists typically respond by accepting that their view requires a preferred frame — perhaps not in conflict with physics if it is not empirically detectable — but B-theorists argue this is an unmotivated metaphysical addition.
Question 3 True / False
McTaggart introduced the A-series and B-series distinction in order to argue that time is ultimately unreal, not simply to describe two competing views.
TTrue
FFalse
Answer: True
McTaggart's famous argument in 'The Unreality of Time' (1908) was that the A-series is essential to time (without it, there is no genuine temporal change or flow), but the A-series is self-contradictory (every event must have all three A-properties — past, present, future — but these are mutually exclusive). Since neither the A-series nor the B-series alone can constitute real time, McTaggart concluded that time itself is unreal. Contemporary philosophers have largely repurposed his framework as a way to describe the A-theory/B-theory debate rather than endorsing his conclusion, but his original intent was eliminativist.
Question 4 True / False
The 'growing block' view is a form of B-theory because it holds that the past and present both exist.
TTrue
FFalse
Answer: False
The growing block view — that the past and present are real but the future does not yet exist — is a form of A-theory, not B-theory. It assigns metaphysical privilege to 'the present' as the cutting edge of a universe that is expanding into the future, and it denies that future times have the same ontological status as the past and present. B-theory (eternalism) holds that past, present, and future are all equally real. The growing block view captures the intuition that the past is 'done' and the future is 'open,' which is a quintessentially A-theoretic commitment.
Question 5 Short Answer
A B-theorist and an A-theorist both agree that the sentence 'Today is March 20, 2026' can be true. What do they fundamentally disagree about regarding that sentence?
Think about your answer, then reveal below.
Model answer: The B-theorist treats 'today' and 'now' as indexical expressions — like 'here,' they pick out a location relative to the speaker without marking any metaphysically privileged position. The sentence is true because the speaker is located at March 20, 2026 in the four-dimensional manifold, just as 'I am here' is true when uttered anywhere. The A-theorist holds that 'now' picks out something genuinely special: the present moment has a unique ontological status that past and future moments lack. The disagreement matters because it determines whether physics needs to recognize an objective 'now' and whether the felt flow of time reveals something about the structure of reality or is merely a perspectival artifact of our temporal location.
The indexicality of 'now' is the crux of the A/B debate. B-theorists analyze all seemingly tensed statements as indexical claims about the speaker's location in a tenseless four-dimensional manifold. A-theorists insist that 'now' picks out an intrinsic, non-relational property of events — being present — that is not reducible to 'occurring at the same time as the speaker's utterance.' This distinction has implications for the philosophy of physics, the metaphysics of identity over time, and the nature of causation.