Trust

If you're not naive and you know you can be bit what can you do:
Trust people, not because you're naive and not because they couldn't betray you and not because you don't know they can betray you but because if you hold out your hand in trust then you're inviting the best part of that person to step forward and that wont happen unless you take that initial step and that's courage, not naivety, so to trust someone once your eyes are open, that's an act of courage and that opens up the world.