The Constraint Model

DIMENSION 13 · TYPE V, MODEL

This is a toy model in the economist's sense. It takes from the itinerary (base document 03) a graph of eighteen named places, the hours 03 gives, two purses, four facts about Bloom's day and one fact about Stephen's, and it lets you route a figure through them against a running clock. It is not a claim about what anyone felt or intended. Its constraints are hard windows and detection events; the novel's are soft and interior. Where the model had to guess, the guess is printed on the line that uses it, marked [assumed], and listed in full below the instrument. You operate it; you do not read it.

Bloom starts with four shillings and ninepence, a funeral he must attend, an advertisement he must place, a house he cannot return to before four, and one man he must not meet. Stephen starts with nothing in his pocket until Dalkey pays him, no obligation at all, and no key. The clock runs from eight in the morning to a quarter to three the next morning, where 03 stops. Nothing you do ends the day early except going home; the day cannot be won, only failed informatively.

Assumptions

Everything below is a modelling choice, printed here in the document flow, not behind a keystroke. Anything not covered by these sixteen lines comes from 03, and the line that uses it says which section.

1. Walking pace 5 km/h applied to the distances 03 states; tram and train about 2½× foot, the funeral carriage about 2×. The multipliers are assumed.
2. Edges exist only where 03 describes a traversal. Where 03 states no distance, the duration is interpolated from relative position and bounded by 03's consecutive-episode clock gaps; every such edge is marked [assumed] on its row and in the edge table.
3. One composed leg: 03 is silent on Bloom between six and eight in the evening. The model sends the documented car south-east from Little Britain Street and waits on the strand. The ledger flags it.
4. The clock is quantized to 5-minute display and 15-minute waits, because 03's own warning is that hours are firm and minutes approximate. Every minute shown here is a rounding.
5. The funeral counts as attended if the figure is at Newbridge Avenue between 10:30 and 11:00, or at Glasnevin between 11:00 and 11:45. Both bounds are assumed; 03 fixes the hours, not the attendance rule — and a dawn visit to the cemetery is not the funeral.
6. The advertisement counts as attempted on a visit to the Freeman's Journal office between 10:00 and 18:00. The office hours are assumed; 03 fixes only the noon visit — and in 03 the renewal is never settled, so the chip says attempted, never placed.
7. The home lockout is a hard wall from 09:30 (the morning's last departure) to 16:00. The novel's constraint is psychological, not physical. And the key is in the other trousers all day (03 §17), so every return is over the railings.
8. The Boylan hazard is his documented sightings only, each active ±30 minutes: the Molesworth-Street sighting ~13:50 (03 §8) placed on the Grafton–Duke node and the fruit shop ~15:00 (03 §10 gives no address) likewise placed there — both placements assumed; the Ormond bar just before 16:00 (03 §11); the front door of Eccles Street at 16:00 (03 §4). His departure from Eccles Street is unstated and is modelled as evening — active to 20:00. No diffuse risk is invented between sightings.
9. Stephen's £3 12s is credited at Dalkey at 10:00, where 03 places Deasy's payment. The dimension specification credits it at the day's start; the model follows 03 and says so.
10. Stephen's gap runs 15:00–22:00 — seven hours, per 03's own sentence. During it his position is unknown, co-presence is indeterminate, and nothing is counted. The Wandering Rocks fragment at three has no address in 03 and is likewise uncounted. Both choices are conservative: they can only lower the crossing counts.
11. A crossing is: same place with overlapping minutes. The second, wider count adds: one edge away within ten minutes. Both are always printed side by side. The 22:00 meeting at Holles Street is tallied apart from both.
12. Spending amounts are placeholders — kidney 3d, soap 4d, lunch 7d, dinner 1s 6d, crubeen 4d, coffee and bun 4d — each marked [assumed] on its ledger line. Bloom's opening four and nine is the dimension's own figure; 03's one money glimpse of him (“eightpence,” Grafton Street, §8) is looser and is not modelled. The real economy of the day is dimension 4's ground, not this model's.
13. Stephen's purse drains 72 pence an hour from receipt — a calibration to two sentences in 03 (“most of it will be gone by midnight”; at Burke's, “by the end of the hour it is gone”), not a claim about who bought what. The drain is flat; the model does not know who is drinking. The flat rate empties the purse about an hour before 03's Burke's sentence does — the calibration is deliberately blunt.
14. The thousand-day policy is uniform over legal moves and the 15-minute wait, except one step along a shortest path when an obligation would otherwise become unreachable. The walker keeps Bloom's constraints, knows nothing of Stephen, and stays out until two, as the book's day does — with one crack: when every other exit from a dead end is closed, the forced step may pass through Eccles Street, which the walker otherwise avoids.
15. The classifier is mechanical and identical for your day, the random days, and the book's: TOWARD — destination hosts an open or upcoming unmet obligation. AWAY — no obligation targeted, and the move departs an active documented hazard or increases graph distance from the nearest one. DRIFT — neither. Waits are drift.
16. Co-presence with a documented Boylan sighting is detected at node resolution. The book can put two men in one building and keep them apart in it; this model cannot see rooms. Where that overstates, the line says so.
17. Constraints here are hard and exterior; the novel's are soft and interior. That gap is the definition of a toy, and the model would rather show it than hide it.

The data, from 03 and only 03

The tables below are rendered from the same constants the instrument runs on — there is one copy of the data, and this is it. Provenance is per entry: [03] where the itinerary states the thing or its clock gaps bound it, [assumed] where a listed assumption produced the number.

The eighteen places

The edges

Stephen's documented day, the timetable the model plays against

Boylan's documented sightings, the hazard track

03's near-misses, the validation target

The replay (key Shift+J) must reproduce this table or say exactly where and why it cannot.

What the model refuses

the model

No map, no streets, no picture of anything: adjacency is the only geography here, because representation is another project's ground and not this one's. No character beyond the two figures and a hazard track: Stephen is a timetable, Boylan is four sightings. And the person who travels furthest in the book does not appear in the model at all — the episode with no hour and no movement has no place in a routing problem. That absence is a confession about what kind of thing this is, and it is the most accurate line in it.