Top
禺 supplies the sound — yú level-tone, no drift. Originally a drawing of a long-tailed monkey,
禺 also carried a faint flavour of 'simian, primitive,' which fits
愚 nicely: a foolish mind, untrained as an animal. Same phonetic and image family:
遇 to meet,
寓 to lodge,
偶 idol,
隅 corner.