Do you think we need evil if there is to be good?

I would agree good and evil event are on a scale rather than seeing them as all the same, if we took away everything we saw as evil we would see things further down the scale just as evil as what we saw evil event such as murder.
For example today many people see capital punishment as how evil humans are but just jump back a few hundred years and you maybe killed just for looking at a high member of society in the wrong way something that is unlikely to happen today.
(I don’t agree with this 100% and I don’t believe good and evil are anything more than feelings)