The youth has within him both a Hamlet and a Saint-Just, both a vacillator and a zealot.
Anything to arouse this personator of our human mutability, this vacillator between doing and letting alone!
1590s, "to sway unsteadily," from Latin vacillatum, from vacillare (see vacillation). Meaning "to waver between two opinions or courses" is recorded from 1620s. Related: Vacillated; vacillates; vacillating.