This article is based on an extensive panel study wherein
the real-time progress of several language changes was mapped
over a period of ten years. Our study suggests that categorical
linguistic features are inclined to remain categorical in the idiolect.
If a speaker, as a child, “learns” a feature with little or
no variation in it, no major changes are likely to take place during
the speaker's lifetime. In other words, new changes rarely
commence in an idiolect later in life. If, however, a speaker adopts a
feature as a variable one, with two or more truly competing variants,
it is possible that the balance of the variants will shift during the
speaker's lifetime. The more equal the proportions of the
rivalling variants are, the more likely it is that one of the variants
will gain dominancy during the speaker's lifetime.The present study has been partially funded
by the Academy of Finland. For assistance we thank the staff of the
Virrat Project at the University of Tampere, Finland.