Jespersen's cycle

[2] The linguist Otto Jespersen began his book with the words:[1] The history of negative expressions in various languages makes us witness the following curious fluctuation: the original negative adverb is first weakened, then found insufficient and therefore strengthened, generally through some additional word, and this in turn may be felt as the negative proper and may then in the course of time be subject to the same development as the original word.The process has since been described for many languages in many different families, and is particularly noticeable in languages which are currently at stage II (both the original and the additional word obligatory) such as French, Welsh, and some dialects of Arabic and Berber.

There are three stages, labelled I, II and III:[3] In Stage I, negation is expressed by a single pre-verbal element: jeoIneNEGdis.say(Old French) jeo ne dis.I NEG say'I do not say'In Stage II both a preverbal and a postverbal element are obligatory: jeIneNEGdissaypas.NEG(modern standard French) je ne dis pas.I NEG say NEG'I do not say'In Stage III the original preverbal element becomes optional or is lost altogether: jeIdissaypas.NEG(modern colloquial French) je dis pas.I say NEG'I do not say'French is well known to use a bipartite negative, e.g. Je ne sais pas: "I don't know", lit.

[4] In both languages, the colloquial register is at a more advanced stage in the cycle, and the first part (ne or ni(d)) is very frequently omitted.

Spoken Brazilian Portuguese is also in differing stages of Jespersen's Cycle, depending on register and dialect.

[6][7] The same development occurred in the other Germanic languages such as German and Dutch, which produced their respective postposed negative particles nicht and niet, first duplicating and eventually ousting the original preposed negative particle *ne / *ni.

[9][10] The Chamic languages, spoken in parts of Cambodia, Vietnam, and Hainan, may also be undergoing Jespersen's cycle.