Endings — 23 of 70

Part 2 - Locking

Section 1 - Multiple locking (in place of Section SR1/9 - Lockability in Standard Rules by Graham Nelson)

[Multiple keys should be able to open a lock; this is not how Graham sees things, so we convince him that it's ok to do so.]

A door can be lockable. A door is usually not lockable.

A door can be locked or unlocked. A door is usually unlocked.

A door has an object called a matching key.

A locked door is usually lockable. [An implication.]

A locked door is usually closed. [An implication.]

A lockable door is usually openable. [An implication.]

A container can be lockable. A container is usually not lockable.

A container can be locked or unlocked. A container is usually unlocked.

A container has an object called a matching key.

A locked container is usually lockable. [An implication.]

A locked container is usually closed. [An implication.]

A lockable container is usually openable. [An implication.]

Lock-fitting relates various things to various things.

The verb to unlock (it unlocks, they unlock, it unlocked, it is unlocked) means the lock-fitting relation.