"All the telephone poles are the same size and the tracks evenly apart. But to the eye they are not. The poles and the tracks get smaller and smaller the farther away they are. This is called the vanishing point."
These might be the exact words of Leonardo Da Vinci in the 15th century if only the railroad had gone past his house.
A still earlier ancestor once noted that all the sides of this house are the same height but B is larger than A or C because it is nearest our line of vision.