The standing A/B disagreement ([§7.2.1](<7.2.1 What is Disputed.md>)) rests on a mistake. A and B *are* the two features Temporality requires, not two descriptions of one. The B-series names the dimension: the ordered manifold along which states stand in earlier-than/later-than relation. The A-series names the passage through that dimension: the directed flow by which a state at one position gives way to a state at the next. A dimension with no passage is a frozen manifold: symmetric, undirected, not Temporality at all, as the structural argument establishes above. Passage with no dimension is undifferentiated change without before and after, which is not Temporality either. Temporality *is* the dimension together with the passage through it.

This dissolves McTaggart's incoherence charge at its root. He argues that the A-series requires every event to be past, present, and future: a contradiction. The contradiction arises only if tense ascriptions are treated as belonging to the same feature of Temporality that carries the earlier-than/later-than ordering. They do not. Tense belongs to the passage; order belongs to the dimension. An event has a fixed position in the B-series and, as the passage sweeps through, is successively future, present, and past from the passage's own perspective. No contradiction arises because the two ascriptions belong to distinct features of Temporality, not to one feature described twice.

The account has a consequence for *now*. All energy has coordinates: everything bearing Physicality (Φ, one of Nature's three structural conditions) is located somewhere in the dimensional manifold. The passage runs through that manifold whether or not anything registers it; the A-series names the passage itself, not its registration. What is distinctive about *now* is that the passage is being registered from inside: when a physical region has integrated enough to track its own position as the passage moves through it. *Now* is not a third feature alongside dimension and passage; it *is* the passage as it registers from within a configuration complex enough to feel itself moving through. There is no *now* without a *here*, and no *here* without a *this-that-persists-to-register-both*. [§7.8](<7.8 Life.md>) develops the mechanism under its proper name: self-modeling (a configuration carrying an internal map of itself that the passage updates as it sweeps through); for Temporality, the narrower point is that the flow does not merely happen to a configuration but is tracked from within it.

Presentism and eternalism make the same mistake from opposite sides. Presentism (only the present exists) absolutizes the passage: it mistakes the directed flow for the whole of Temporality and denies the reality of the dimension through which the flow runs. Eternalism (all times are equally real) absolutizes the dimension: it mistakes the ordered manifold for the whole of Temporality and denies the reality of the passage. Both errors share the same structure. They take one of the two features Temporality requires and try to make it do the work of both. The correct picture is the composition: the dimension is real, the passage is real, and Temporality is what they together constitute.

The composition carries two commitments worth marking. The passage is metaphysically real, not a perspectival projection: the directed flow obtains whether or not it registers, and what registration adds is the *now* feature treated above. No moment is metaphysically privileged as *the* real one against which the others are unreal: the dimension is real along its full extent, and tense-privileging is configurational register, not a feature of the medium itself. A B-theoretic reduction of passage to indexical content is in disagreement with the composition on this point and not absorbed by it. To that extent the composition is not a neutral dissolution of the A/B dispute but a substantive position within it: it sides with the A-theorist that passage is mind-independent and contradicts the reductive B-theorist rather than vindicating both. The composition claims that dimension and passage are both required features; the contested premise it defends (and must defend on its own merits) is that passage is real independently of whether it is registered. And the question whether the universe *began to exist* admits two readings the composition lets us mark separately: a quantitative reading (how far back along the dimension does the passage run) engaged at [§5.1.2](<5.1.2 Cosmological Argument.md>), and a categorial reading (a moment-prior-to-T from which T began) foreclosed by Parasitic Negation on T (§[§2.1.5](<2.1.5 The S5 Bottleneck.md>), 5.1.6). Kalām's traversal argument operates on the quantitative reading; the fall-narrative's t₀ operates on the categorial reading.

Tensed and tenseless are therefore not rival metaphysics of Temporality. They name the two features any structural account of Temporality must supply: the ordered manifold along which states are arrayed, and the directed passage by which configurations move through it. As in [§7.3](<7.3 Space.md>) and [§8.8](<8.8 Meaning.md>), the appearance of long-standing division in the tradition is not evidence of rival subject matters. It is evidence that one self-sufficient subject matter has distinguishable features that different traditions have tracked in isolation.


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← [7.2.1 What is Disputed](<7.2.1 What is Disputed.md>) | [7.2.3 What is Predicted](<7.2.3 What is Predicted.md>) →
