The way the “abrupt change” at around 1430 is presented in the Hockney book, and the way we look back on it as history, is what makes the improvement in drawing at that time seem almost overnight. But, in reality it was slower and occurred over several lifetimes, although not much more than that, perhaps. When observing “several lifetimes” through the veils of intervening centuries, it seems abrupt, indeed.
The change probably worked like this: some artists during what later came to be known as the early Renaissance, started to truly observe the material world. Prior to that time, depiction of the real world was not an especially important aspect of Western art. What was important was the afterlife, so art was subservient to that. It was based on iconography, on formulae, on ideals, etc. and not on a concern with corporeal reality. In the Renaissance period, however, just as European thought was becoming increasingly humanist, so too was that thought being incorporated into the consciousness of artists. Then, just as today; artists were not living in a vacuum, separated from reality. They would have been as diverse as any group, and likely an intelligent and curious bunch, for the most part, so they would have been interested in seeing how to use this newfound “freedom” of thought to improve upon and be reflected by their art. One consequence was an increased concentration on “what things look like” -- based on real world observation.
Even with that, these improvements took the greater part of a 100 years to materialise. That is only a few generations, yes, but it is not “overnight” on a human scale. The developments in art can be easily accounted for in terms of human effort, intelligence, and talent, rather than on mirrors or lenses and the like (which also were developed by human effort, intelligence, and talent at around that time). What is being suggested by the coincidence of these developments is “possible”. But, since it is not a necessary component of the mechanism of artistic development during that period, as I outline above, and nor is there any hard evidence, it thus remains “improbable”, at best. It simply doesn’t stand up as a good theory.
Juan
