The Gestalt principles of form perception include figure-ground, proximity, similarity, continuity, closure, and simplicity.
The Gestalt emphasis is still felt in the study of perception, as they had useful insights that have stood the test of time, raised important issues, etc.
In visual perception, the images projected on the retinal are distorted versions of their actual 3D counterparts. So how do we get an accurate view of the world? One explanation is that people are constantly making and testing hypotheses. A perceptual hypothesis is an inference about what form could be responsible for the pattern of sensory stimulation, often guided by context.