Thinking Outside of the Box

"You just cannot think outside the box,
Since you have no perspective," he mocks.
But that's harsh and not fair
Since I live as a Square —
Depth perception gives hypercubes shocks!

The English schoolmaster and theologian Edwin Abbott Abbott (1838–1926), in his 1884 satirical novella Flatland: A Romance of Many Dimensions wrote about a world (Flatland) of two-dimensional beings. Abbott, in part, intended its use as an allegory of certain emerging mathematical, sociological and metaphysical ways of thinking.

The hero of the novella is the Square who has a dream about Lineland (a one-dimensional space) and his conversations with its inhabitants who cannot perceive of a world of two dimensions. This opens his mind and the Square is then visited by the Sphere, a three-dimensional being of Spaceland. To the Flatlander's concept of nature the Sphere is a supernatural entity.For a conventional Flatlander that lived as a Square, the description of a Box would be metaphysical nonsense, according to his natural perception of reality. To entertain the concept of a Box requires the ability to transcend the limitations of two-dimensional perception (in this case depth perception). The Square's real three-dimensional shape might be a Cube (a 3D Box).