arbitrariness arbitrariness /ˈɑːrbəˌtrɛriːnəs/

noun

1. The trait of acting unpredictably and more from whim or caprice than from reason or judgment  ( arbitrariness , capriciousness , flightiness , whimsey , whimsicality , whimsy )
   the trait of acting unpredictably and more from whim or caprice than from reason or judgment
    I despair at the flightiness and whimsicality of my memory
   I despair at the flightiness and whimsicality of my memory