the letter c in esperanto
c = ts in English "bits."
This has given rise to much criticism. The same sound is also expressed by the letters ts. Why depart from the Esperanto principle, "one sound, one letter," and have two symbols (c and ts) for the same sound?
A standing difficulty of an international language is: What equivalent shall be adopted for the c of national languages? The difficulty arises owing to the diversity of value and history of the c in diverse tongues. Philologists, who know the history of the Latin hard c and its various descendants in modern languages, will appreciate this.
(1) Shall c be adopted in the international language, or omitted? If it is omitted, many useful words, which it is desirable to adopt and which are ordinarily spelt with a c, will have to be arbitrarily deformed, and this deformation may amount to actual obscuring of their sense. E.g. cento = hundred; centro = centre; cerbo = brain; certa = certain; cirkonstanco = circumstance; civila = civil, etc. Such works would become almost unrecognizable for many in the forms kento, sento, tsento, etc.
(2) If, then, c is retained, what value is to be given to it? The hard and soft sounds of the English c (as in English "cat," "civil") are already represented by k and s. Neither of these letters can be dispensed with in the international language; and it is undesirable to confuse orthographically or phonetically c-roots with s- or k-roots. Therefore another value must be found for the symbol c. The choice is practically narrowed down to the Italian soft c = ch, as in English "church," and the German1 c = ts in English "bits." Now ch is a useful and distinctive sound, and has been adopted in Esperanto with a symbol of its own: ĉ. Therefore ts remains.
1Also late Latin and early Norman French.
(3) Why not then abolish c and write ts instead? For answer, see No. (1) above. It is a worse evil to introduce such monstrosities as tsento, tsivila, etc., than to allow two symbols for the same sound, ts and c. International language has to appeal to the eye as well as to the ear.
This matter of the c is only one more instance of the wisdom of Dr. Zamenhof in refusing to make a fetish of slavish adherence to rule. Practical common-sense is a safer guide than theory in attaining the desired goal—ease (of eye, ear, tongue, and pen) for greatest number. In practice no confusion arises between c and ts.