Vacillate (VA sill ayt)-to waver indecisively between one course of action or opinion and another

Examples:

Benjamin cannot decide who to vote for; he keeps vacillating between the two candidates.
If you keep vacillating about whether you want this job or not, someone else will take it from you.

Quote:
A fool thinks himself to be wise, but a wise man knows himself to be a fool.
William Shakespeare

to me this quote mean that the fool known also as the man is vacillating betweent him being wise and him being a fool he to himself can be one in the sme thing