“The glass is ½ empty. The glass is ½ full”. Is often illustrated to see two different ways of thinking.
Remember the blue dress controversy of 2015? Is the dress white and gold or black and blue?
It all depended upon how your eyes translated the image to your brain. It was based on perspective.
Each one of us has a different perspective. We base these perspectives on past experiences, what we believe to be true, and what others have told us is true.