“It’s all in the mind.”― George Harrison

Well, what John Harrison said is on point. Different people perceive different things. Every mind perceives things uniquely. Most of the people look at phenomenons from a single angle only, while some enlightened minds consider every aspect and angle. The kind mentioned latter is nearly extinct.

Our reality is composed of what we perceive(or want to perceive). According to a pessimist, the glass of what will always be half empty, in case of an optimist its the other way around.