The linguistic positivity bias in English literature of different genres: A diachronic study across 700 years

Previous studies have found that human beings have a positive tendency, which is labelled as the linguistic positivity bias. Such a bias has been examined and confirmed in literary works such as children and youth literature. However, such literature works are written for children and adolescence and thus they are naturally more positive. It is necessary to examine the bias based on literature of other genres that are written for adults. In addition, it remains unexplored how the positivity bias has evolved over a long period of time and how the social and cultural factors interact with literature works to shape the bias. To address the aforementioned issues, the present study aims to examine the linguistic positivity bias in English literature across three genres (i.e., novels, plays, and poetries) and their temporal trend across 700 years. The results show that most of the literature works have a positive tendency and no significant difference is found among the three genres regarding the sentiment values, which further confirms the linguistic positivity bias in human languages. However, it is worth noting that the linguistic positivity bias displays a decreasing trend. Possible explanations are provided for such a trend from social and cultural perspectives.