Perception is projection (2)
In order to understand our world we attempt to apply meaning to it.
Or, if we accept that each of us is a unique human being and that each person's map of the world is also unique, in order to understand our worlds we attempt to apply meaning to them - each of us attempts to apply our own meanings to our world in order to understand it.
In order to understand other people we attempt to apply meaning to their actions, their behaviours and their communications.
However, as incredible as we are as human beings we are limited in our ability to truly understand other human beings, why they do the things they do, why they say the things they say and what they truly mean when they do and say them.
The only way we could truly understand another human being would be to actually become them - to be born as them, to grow up as them, to have exactly the same experiences, thoughts, environment and influences as them.
Tools which we use to get around these limitations include our imagination and our ability to use our map of reality to project meaning onto external objects and events.
These are useful tools but they too are limited in that the projections we make, the meanings we ascribe to the world around us and our understandings of it, are generated from within - we project ourselves onto our world, we see things not as they are but as we are.