What is another word for mercurialness?
Pronunciation: [mɜːkjˈʊɹɪəlnəs] (IPA) 
Mercurialness is a complex concept that refers to a person's unpredictability, volatility, and capriciousness. Synonyms for this word include fickle, moody, erratic, unstable, volatile, fluid, ever-changing and unpredictable. These words all describe people who are prone to sudden mood swings or changes of opinion, often without warning or explanation. A mercurial person can be charming and delightful one day, and hostile or withdrawn the next. Other synonyms for mercurialness are impulsive, quick-tempered, temperamental, changeable, and flighty. Whatever word you use, there is no denying that mercurial people can be challenging to deal with, but they can also be incredibly creative, spontaneous, and passionate.
