Humans are quintessentially three-dimensional beings. Whether we consider our everyday surroundings (a chair, a dog, the neighbor on the fourth floor…), real objects that we picture without having them before our eyes (the teddy bear from our early childhood, our lungs…), or even imaginary objects and environments that each of us can conjure up through imagination alone (the "Na'vi" in the film Avatar (2009) existed in James Cameron's mind before reaching our screens), they all have one thing in common: they are three-dimensional objects.
Details of cave paintings in the Lascaux cave (Dordogne), around 18,000 BCE.
