Example sentences:

Ramayana:  When Maricha saw Ravana return so quickly, he feared the worst knowing that Ravana was so capricious that he could in a moment reject all good advice and act according to his whims.

Mahabharata:  Although Dhritarashtra was not as vicious as Duryodhana, his attachment to Duryodhana made him capricious because he couldn’t displease Duryodhana.

Bhagavad-gita:  The mind is so capricious that the very thing it loves today, it may hate tomorrow.