This chapter is concerned with what we know about the status and the history of discourse markers. The chapter provides a detailed discussion of the various hypotheses that have been proposed to account for the rise of discourse markers. It is argued that none of those hypotheses is entirely satisfactory, pointing out a number of shortcomings characterizing such earlier approaches. The conclusion reached in the chapter is that discourse markers exhibit a catalog of grammatical properties that are hard to explain on the basis of those approaches.

In this chapter, the framework proposed in Chapter 2 is applied to the history of English. The discourse markers studied are after all, anyway, I mean, if you like, if you will, instead, like, no doubt, right, so to say/so to speak, well, and what else. The findings presented are in support of the hypothesis proposed in Section 1.5, according to which discourse markers are the joint product of two separate mechanisms, with each of the mechanisms accounting for specific properties of discourse markers.

In this chapter, the framework proposed in Chapter 2 is applied to the history of French. The discourse markers studied are à la rigueur, à propos, à ce propos, alors, en fait, au fait, and enfin. The findings presented are in support of the hypothesis proposed in Section 1.5, according to which discourse markers are the joint product of two separate mechanisms, with each of the mechanisms accounting for specific properties of discourse markers.

In this chapter, the framework proposed in Chapter 2 is applied to the history of Korean. The discourse markers studied are icey, makilay, maliya, and tul. The findings presented are in support of the hypothesis proposed in Section 1.5, according to which discourse markers are the joint product of two separate mechanisms, with each of the mechanisms accounting for specific properties of discourse markers.

In this chapter, the framework proposed in Chapter 2 is applied to the history of Japanese. The discourse markers studied are dakedo, demo, douride, ga, jijitsu, sate, and wake. The findings presented are in support of the hypothesis proposed in Section 1.5, according to which discourse markers are the joint product of two separate mechanisms, with each of the mechanisms accounting for specific properties of discourse markers.