What allows us to perceive depth when we are looking at something with both eyes?

The ability to perceive depth when using both eyes primarily relies on binocular disparity. This phenomenon occurs because each eye views a slightly different image due to their separation in position. The brain processes these two images, which helps it gauge the distance to objects. The difference in the images, or disparity, is crucial for depth perception as it provides a three-dimensional view of the environment.

When the brain combines the slightly varied perspectives from each eye, it can accurately assess how far away objects are based on the degree of disparity. This depth perception method is particularly effective for nearby objects, making binocular disparity a key mechanism in visual processing and spatial awareness.