Universal 1328:
- Original
 - A historical tendency toward phonological symmetry is universal.
 - Standardized
 - A historical tendency toward phonological symmetry is universal.
 - Keywords
 - phoneme inventory
 - Domain
 - phonology
 - Type
 - unconditional
 - Status
 - diachronic
 - Quality
 - almost absolute
 - Basis
 - unspecified
 - Source
 - Hockett 1963: 25
 
- Counterexamples
 
Cf. #1333.