  Growing polarisation in society caught the attention of the scientific
community as well as news media, which devote special issues to this
phenomenon. At the same time, digitalisation of social interactions requires to
revise concepts from social science regarding establishment of trust, which is
a key feature of all human interactions, and group polarisation, as well as new
computational tools to process large quantities of available data. Existing
methods seem insufficient to tackle the problem fully, thus, we propose to
approach the problem by investigating rhetorical strategies employed by
individuals in polarising discussions online. To this end, we develop
multi-topic and multi-platform corpora with manual annotation of appeals to
ethos and pathos, two modes of persuasion in Aristotelian rhetoric. It can be
employed for training language models to advance the study of communication
strategies online on a large scale. With the use of computational methods, our
corpora allows an investigation of recurring patterns in polarising exchanges
across topics of discussion and media platforms, and conduct both quantitative
and qualitative analyses of language structures leading to and engaged in
polarisation.
