That's a really interesting approach to interactive fiction!

According to the manual, the world is defined with assertions like these:

The wood-slatted crate is in the Gazebo. The crate is a container.

Mr Jones wears a top hat. The crate contains a croquet mallet.
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The manual also explains that "the world described by these assertions is the starting condition of the game: what happens when play begins is another matter. If somebody picks up the crate and walks off with it, then it will no longer be in the Gazebo. Mr Jones may remove his hat".

Really really interesting.