The Diachronic Comparative Study Of Can And Neng In The Development Of Epistemic Modality

The study of modality can be traced back to the ancient Greek period, which is a subject with much attention in the academic field. Due to its complexity and the close connection with human cognition, it has been concerned by many different schools. Most of the modal words are polysemous, expressing speakers' emotion and attitude, as well as inference and deduction of the proposition.According to statistics, can and neng are most frequently used in the category of modality. However, most scholars have been synchronically studied them in two separate modal systems. In particular, the issue that whether can and neng have generated the epistemic meaning, expressing the factual status of the proposition, is still controversial. Therefore, in order to improve the deficiency in previous studies, the thesis attempts to diachronically investigate and make a comparison of the grammaticalization process of can and neng, in the aspect of semantic change, cognition as well as the syntax. Methodology used in the study are description and explanation, the qualitative and quantitative approaches, statistic analysis with the help of several representative corpora (OED, BNC, COHA, COCA, CCL, and CNCORPUS), and diachronic study with the time line of the Modern English and Modern Chinese period.After a thorough analysis, it is easy to draw the conclusions:firstly, the grammaticalization process of can and neng are similar in general, as in the semantic development: at the very beginning, they all refer to the general ability of agent, both physical and mental power; and then develop into the possibility for the agent to complete certain action; after that, the meaning changes into permission and obligation, which are influenced by the social regulation, morality, or authority; later, they all refer to the deduction of the proposition's truthfulness, based on speakers' knowledge. Besides, the development of can and neng as modals are similar, which is from dynamic modality into deontic modality, and then finally as epistemic modality. However, there still exist several distinctions under their similarities, which are in the following aspects:development of meaning in the Early Modern period; development of their negative structure; dynamic change of their polite mood and collocation. Last but not least, the final results not only reflect that both can and neng have generated as an epistemic modality, but metaphor and generalization are the two effective mechanisms of grammaticalization. Hope the present study would help the learners to understand the characteristic and general rule of Chinese and English language.