# O03 · A seed-library key that needs a decision

**FICTIONAL PLAN · deliberately ambiguous key**

The supplied picture has an envelope shelf and an empty-envelope tray. A square marks each. Its printed key says square = envelope shelf AND square = empty-envelope tray. A pretend borrower asks which place holds envelopes to borrow. The key is ambiguous; the words label two different jobs. A child can propose a consistent new mark/word relation. This does not report a real library problem; no seeds are handled or swallowed.

| Label | Supplied marker |
| --- | --- |
| envelope shelf | square |
| empty-envelope tray | square |

This table gives labels/key information, not a physical travel direction.

**Key:** square = envelope shelf; square = empty-envelope tray.

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