Rubuta wani ɗan gajeren sakin layi na labari da aka ba da batun da ke gaba:  Mutum X yana karanta game da halayyar ɗan adam
Tabbas, ga ɗan gajeren sakin layi: Sagan yana sha'awar fahimtar dalilin da ya sa mutane suke yin abin da suke yi. Don samun fahimta game da wannan batun, Sagan yakan karanta littattafai da labarai game da halayyar ɗan adam. Ba da daɗewa ba, Sagan ta karanta wani littafi game da ilimin jan hankali, wanda ya ba da wasu bayanai masu ban sha'awa game da yadda mutane suke jan hankalin juna.