The Time–axis Phenomenon

It is shown that presuppositions and implications associated with verbs distribute themselves relative to the time-axis (action-time) of the verb. Presuppositions pertain to the time preceding this time-axis, while implications pertain to the time following the time-axis. The semantics of two universal verb classes, modality verbs (M-verbs) and cognition verbs (C-verbs), is analysed in light of these findings. Two widespread diachronic processes of sense extension are studied. One involves the development of sentence modalities from M-verbs. It is shown that a great amount of predictability exists in this process, and that the type of tense aspect marker likely to arise from an M-verb may be inferred, with great accuracy, from the specific presuppositional and implicational structure of the precursor verb. A considerable degree of predictability is also shown in the development of M-verb senses from C-verbs. It is suggested that our temporal and aspectual notions, including our notions of time, negation, certainty, and possibility, are already present in the semantic structure of verbs. Diachronic extensions of verb-senses merely serve to illuminate this.