• The principle of Emotion says that making messages full of emotional valence and arousal affect (e.g., describing a miserable situation or a happy moment) can make people care and act, e.g., "The picture of widow Bunisia holding one of her children in front of her meager home brings tears to my eyes..", similar to Sentiment and Politeness used by Althoff et al., (2014) and Tan et al., (2016), and Pathos used by Hidey et al., (2017).
in this context, we did not observe enough instances of them.