The problem with 'seeing is believing' is that our eyes can be deceived. There are many perception exercises available on the net, designed to trick us into seeing one thing, but later it has become something else. The film Shallow Hal was about a guy who was vain, where he was driven purely by the way a person looks. After meeting Tony Robbins (author of Awaken the Giant Within) in a lift, he could only ever see the good in people, no matter how they appeared to look on the outside. Even his relationships became deeper, well for a comedy film. Remember cynics it's only a film!
That's the problem when we hold great weight in what we can see, our only experience is at face value. Dig a little deeper and we can found out so much more about a person. Doesn't that make so much sense, but why don't we apply it in our life? Could it be that we only see, what is inside of us?