屁股決定腦袋

1. • lit. the butt governs the head (idiom)
2. • fig. where one stands depends on where one sits
3. • one's views are shaped by one's circumstances

Character by character

• 屁(pì)fart
• 股(gu)thigh
• 決(jué)decide
• 定(dìng)fix
• 腦(nǎo)brain
• 袋(dai)pouch