The passenger realized that their hat was lacking.

The conductor realized that the world's axis had shifted imperceptibly
w/r/t galactic north.

The passenger realized that seven flies were doing the fly equivalent
of the Mambo on a windowsill.

The conductor realized with a nervous sigh that everyone who ever
loved him was a pathological liar, and that he was not entirely unsure
that this bothered him.

The passenger realized that all trees were expressions of the same
Platonic tree, except for elms, all of whom can go fuck a knothole,
for all he cared.

The conductor realized that his own hat was lacking, and
simultaneously realized that his hat was stupid anyway and its lack
was nothing to be sad about.

The passenger realized that his ticket was in his hat, which by now
was probably floating somewhere around the crab nebula, or possibly
Philadelphia, which are basically the same thing, if you don't think
about it, which he didn't.

The conductor realized the passenger was naked, except for a hat
covering his genitalia, which he seemed to be unaware of.

The passenger realized that, assuming the correctness of string
theory, which posits that all matter is composed of tiny, vibrating
strings, he was almost certainly a F#.

The conductor died.

The passenger merged with the cosmos, briefly remembering his
now-silly anxiety over his lacking hat.