The two most characteristic features of perspective are that objects are smaller as their distance from the observer increases; and that they are subject to fore-shortening, meaning that an object's dimensions along the line of sight are shorter than its dimensions across the line of sight.
Plato was one of the first to discuss the problems of perspective and medieval artists in Europe, like those in the Islamic world and China, were aware of the general principle of varying the relative size of elements according to distance, but it wasn't until about 1413 that Filippo Brunelleschi defined the geometrical method of perspective, as used by today's artists. Click here to watch a video clip on the history of perspective and how it works.
As for my own perspective on the world, a lot of people and events from the distant past now loom larger in my mind than ever before. It's called memories and they flash by as I ponder the sad state of the world and the even sadder state of my pedicure.
