Two views, one world
Each eye has a slightly different view. The brain uses the difference, along with other clues, to judge depth.
Why do nearby objects shift more between two viewpoints?
Try the idea
Your brain combines the view from each eye with perspective, size and movement. Judging depth uses several clues at once.
Move the foreground post between the two viewpoints. Nearby and distant objects shift by different amounts.
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Oxford Eye Hospital: orthoptics