A Constraint on the Use of -te shimatta

Why does a Car Navigation System Never Say Mokutekichi ni tōchaku shite shimaimashita?

Abstract

This paper reveals a constraint on the use of -te shimatta. We will focus on -te shimatta, i.e., the past tense form of -te shimau, following the main verb relating what happened in the real world.

The past form -te shimatta has a modal implication that what happened was different from what was expected. This implication results in the constraint that the speaker who uses -te shimatta should give information which helps the hearer to understand how exactly what happened was different from what was expected. This paper bases these claims on three investigations: (1) analyses of the contexts of -te shimatta in a conversational corpus, (2) interviews with Japanese native speakers as to the naturalness of relevant sentences in different contexts, (3) instructions for native speakers to make up conversational sentences with -te shimatta.

A car navigation system never says Mokutekichi ni tōchaku shite shimaimashita ‘We have [unexpectedly] reached the destination', because the announcement violates the above mentioned constraint in two respects. First, the system is not concerned with whether or not what happened was different from what was expected. Second, because of its function, reaching the destination has nothing to do with unexpectedness.