10-2g2c Indexes are physical because they merely ‘indicate’ and hence do not require culture. Symbols are cultural. Put differently, indexes are analog and symbols digital.

10-2g2c0 A system is universal if it contains enough expressibility to represent anything. It can do anything and everything.
10-2g2d Science symbolizes physicality beyond parochialism (from seen to the unseen)

10-2g2 Culture invents symbols, and the core of language is the symbol
Indexes are parochial-analog signs. Symbols are universal.
Being arbitrary and contingent means it’s universal!
Universality
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