lit. Sichuan dogs bark at the sun (idiom); fig. a simpleton will marvel at even the most common things / alludes to the Sichuan foggy weather where it's uncommon to see a sunny day
short name for Sichuan 四川[Si4 chuan1] province / one of the Three Kingdoms 三國|三国[San1 guo2] after the Han dynasty, also called 蜀漢|蜀汉[Shu3 Han4], situated around what is now Sichuan province