Navigation is the calculation of position and direction.
The fundamental aim and working principal of the computer are much about navigation than usually missing. Many mechanical aids to calculation and measurement were designed for astronomical and navigational use.
Perception which is constitute from all former experiences, skills, concepts, misconceptions, thoughts and generalisations. The perceptual field, which is the established model of objective reality, of the real world around the subject. It is where the subject finds the background for perception.