The Ambiguous West Door
Memo to staff, Riverton High: 'Because the north stairwell is being repainted from Monday through Wednesday, students whose first class meets on the third floor should use the east stairs. Students arriving before 8:15 may enter through the west door only; the west door is the only entrance whose card reader is working that week. Teachers supervising morning study hall need not check passes but must record attendance by 8:30. Any student who has not collected a new locker assignment by Wednesday keeps the old locker until the following Monday.'
Two teachers read the second sentence differently. Alvarez: the west door is the only door students may use before 8:15. Bhatt: only students arriving before 8:15 may use the west door.
1. Which reading does the sentence's syntax actually support, and why does the other reading feel available?
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Alvarez's reading is the one the syntax supports.
'Only' is a focus-sensitive word: it restricts whatever constituent it sits next to. Here it is attached to 'the west door' at the end of the clause, so the restriction lands on the door: the west door is the sole permitted entrance.
Bhatt's reading would need 'only' in front of the subject, where it would restrict the people:
- Bhatt's policy: Only students arriving before 8:15 may enter through the west door.
- Alvarez's policy: Before 8:15, students may enter through the west door only.
Bhatt's reading feels available because sentence-final 'only' is often used loosely in speech, and because a listener who knows the card reader is broken may assume the sentence is about who is allowed, not which door. That is context guessing, not parsing. The word order is decisive, and the card-reader clause on the other side of the semicolon also points at the door.
2. A student arrives at 8:20. Under each reading, what may the student conclude, and what does the memo not settle?
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Under Alvarez: the west door is closed to the student at 8:20. The memo does not say which entrance replaces it, so the student knows only that the west door is not sanctioned for them; the memo is silent about every other door rather than forbidding them.
Under Bhatt: the student is not in the permitted group at all, so the west door is closed to them whatever their arrival time would have been.
Notice the readings differ for a different population. Alvarez leaves 8:20 arrivals without an entrance; Bhatt leaves all post-8:15 arrivals without one, including those who queue at 8:14 and reach the door at 8:16.
The memo does not settle the practical question (where should an 8:20 arrival go?). That is a gap in the policy, not something to be inferred from tone. A reader's call is to follow the syntax for interpretation and treat the missing entrance as a question for the office.
3. Rewrite the sentence so the ambiguity is gone, giving one version for each intended policy. Add no new rules.
Read the worked answer
If the door is the restriction (Alvarez):
Before 8:15, students may enter only through the west door.
If the people are the restriction (Bhatt):
Only students arriving before 8:15 may use the west door.
Both rewrites pull 'only' next to the constituent it is meant to restrict, which is the whole fix. The first says nothing about which door is available after 8:15, and the second says nothing about what anyone may do after 8:15 - each is silent exactly where the original was silent.
A rewrite that adds information ('all other doors are locked until 8:15') would be a policy change, not an edit, and should not be smuggled in under the heading of clarity.