As a magician, I must strive for balance. For in that state of balance, moving in any direction at all requires much less force than were I leaning to one direction and then trying to move the opposite way. From a place of balance, movements are smooth and directed.
That being said, some folks seek this balance by encountering opposites. They may remove themselves from monogamy and become sluts for a while. Thereby, locating the balanced relationship between their spirit and sex, whatever that may be on the continuum.
However, these things are really not opposites. The opposite of dog is not cat but not-dog. The opposite of love is not hate, but not-love.
I know some that reject society and therefore what society normally calls "good" thinking that behaving in stark opposition to what society expects of them is being enlightened. No, it is merely the inverse portion of the same slavish response. The opposite of a societal norm is the non-existence of the norm within or non-responsiveness to that norm in any way.
Those that feel they must be evil to balance the good are still reacting to good. This is not balance. The opposite of good is not evil, but not-good.
Darkness is not evil, but ignorance. Evil is not darkness but malicious destruction for its own sake or destruction without the purpose of regrowth.
Read not this post to agree or disagree but instead consider the extremes of behavior we engage in and the mislabeled pairs of opposites we use. Contemplating these things may be of value.