三個世界

三 = 一 + 二 : Mnemonic symbol: a Cartesian coordinate system with three (三) axes.

Socrates (s-) is performing in front of the anthill (-an1). He created an electrical flute by attaching a large capacitor (二) to the flute (一), so that he can get the attention of all the ants. Moreover, he's balancing on a Cartesian coordinate system (三). Unfortunately, only three (三) ants stop to watch the performance.

个 = 丨 + 人 : Mnemonic symbol: Neanderthal Man (人). Neanderthal Man (人) needs to use the elevator's bathroom (e4) but it's occupied by Guy Fawkes (g), and there's only space for one individual (个). Impatiently Neanderthal Man knocks on the door using his dinosaur bone (丨).

世 = 廿 + L : Mnemonic symbol: the WTO or WHO.

Sherlock Holmes (sh) is cleaning a flower pot (廿) under the shower of the space station's bathroom (Ø4) with a loofah (L) because he didn't quite understand a poster next to the shower from the WHO (世) explaining dangers arising from different germs.

In this case, L is for loofah.

界 = 介 + 田 : Joan of Arc wants to leave this world and sets up a rocket launch field in the elevator's bathroom. The field looks like a normal crop field, except that there's a rocket in the middle and that the Joan of Arc marked the boundary with white and red tape.