Earlier quoted context omitted.
FWIW, Replacing "th" with "θ" would really be a "re-placement": Theta and the "voiced dental fricative"[1] were smeared together in Old English long ago.[2] I.e. "there" and "theater" are two different "th"'s.[3] [1] https://en.wikipedia.org/wiki/Voiced_dental_fricative [2] https://en.wikipedia.org/wiki/Th_(digraph)#Voiced_fricative_... [3] English speakers: if you pay attention to how you speak those two words you'l…
I can't think of any pair of English words that are distinguished by a voiced vs unvoiced dental fricative at the same location, c.f. 'sue' and 'zoo'. Does any such pair exist?
- "thy" and "thigh"
- "either" and "ether"