The Yin Yang symbol can be seen as goodness and noble dark, for the need to protect those we love is a necessary part of love. In that way, the entire symbol represents the types of love. Evil is something different and it is not a part of the symbol because the world can exist without it. Pure peaceful and nurturing love will always need a way to access noble dark for protection, and noble dark will always need access to pure and nurturing love to survive, and so, as the symbol shows, they do belong together.
The messenger was asked about Yin and Yang, she smiled and replied. "I've always felt an attraction to the yin yang symbol. To me it's always meant caution and hope. Caution because even in the purest of hearts there is a seed that can become greed and vanity, that can use fear to gain power. Hope that even in the blackest of hearts there is still a seed of purity that can grow if nurtured in the right way. In Chinese traditional medicine they encourage one to step back from life and understand how your beliefs, thought patterns and the way you are living cause unwellness of body and mind and I feel that this is approach is required for all societies - to step back, to look at life from everyone's perspective but starting from the most vulnerable in that society - in many places that means women and girls. The only place for fear in the life of an enlightened human is the fear of the old selfish ways reemerging, the ones that are currently destroying the planet on which we all depend. Enlightened people learn to live only through love and positive emotions, being safe in the knowledge that a true noble defence (never attack) is an act of love and Love makes us strong and whole."