Only one, because a parish is not a denomination, a diocese is not a denomination, a rite is not a denomination. All share ONE set of doctrines, so what you SAY is a straw man fallacy. Ok.
According to the
Dictionary of Christianity in America [Protestant] (Downers Grove, IL: Intervarsity Press, 1990): “As of 1980 David B. Barrett identified 20,800 Christian denominations worldwide . . .” (that was 42 years ago)
(“Denominationalism,” p. 351). I have this book, so I have seen this with my own eyes. Barrett “classified them into seven major blocs and 156 ecclesiastical traditions.” This is from
Oxford World Christian Encyclopedia, 1982, of which he is the editor.
Also, according to United Nations there were over 23,000 competing and often contradictory denominations world-wide (World Census of Religious Activities [U.N. Information Center, NY, 1989]). This was cited in Frank Schaeffer’s book
Dancing Alone (Brookline, MA: Holy Cross Press, 1994), p. 4. Schaeffer is Orthodox.
The 1999
Encyclopedia of Christianity has this to say: “In 1985 David Barrett could count 22,150 distinct denominations worldwide.” {edited by E. Fahlbusch, et al., Grand Rapids, MI: Eerdmans, 1999, vol. 1, p. 800, s.v. “Denomination.” David B. Barrett is the statistical editor}
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