Wednesday, June 11, 2008

Book chapter


This is a draft of another chapter for my book. The working title of the book is Artificial Creativity: The Thousand Year Quest to Build a Creative Machine.


Kaleidoscope


In 1817, Sir David Brewster patented the kaleidoscope. Others had noticed the effect of two mirrors meeting at an angle before, as recounted in this selection from a 1818 article in The Edinburgh Magazine and Literary Miscellany:

The repetition and reversion of images in a glass is noticed in the Masfiti Naturalis of Baptista Porta, a Neapolitan nobleman, who flourished about the latter part of the sixteenth century, and was distinguished for his zeal in promoting philosophical pursuits…
In the Ars Magna LucĂ­s et Umbra of Kircher, printed in 1646, we have an account of the same circumstance, and also of the repetition of the sectors round the centre of the circle:
“A wonderful property,” says he,” and one which has not, as far as I know, been observed by any one, is exhibited with two specula, so constructed as to open and shut like a book; and placed on any plane in which you have described a semicircle divided into its degrees. For, if the point in which the specula meet be placed in the centre of the semicircle, so that the side of each speculum shall stand upon the diameter, the image of an object will only be seen once, and two objects will appear, one without the specula, the true one,—and one within, the image. But if the sides be placed at an angle of 120°, you will see the image of the object within the specula twice, that is, along with the real image, three objects But if the specula intercept an angle of 90°, you will see the circle divided into four parts, and four objects; in the same manner, at an angle of 60°, you will see a hexagon with six objects.”
He then applies the principle to some curious contrivances which, by his own account, filled his spectators with astonishment. With one candle he shows how to make a complete chandelier. “With angles of 120°, 72°, and 45°, you will see,” says he, “with no less delight than adimration, a chandelier with three, with five, and with eight branches.”


When Brewster showed his prototype kaleidoscope to manufacturers of optical instruments, pirate copies began cropping up all over the London and soon spread around the world:


You can form no conception of the effect which the instrument excited in London; all that you have heard falls infinitely short of the reality. No book and no instrument in the memory of man ever produced such a singular effect. They are exhibited publicly on the streets for a penny, and I had the pleasure of paying this sum yesterday; these are about two feet long and a foot wide. Infants are seen carrying them in their hands, the coachmen on their boxes are busy using them, and thousands of poor people make their bread by making and selling them. (letter from Brewster to his wife, May 1818)


The kaleidoscope allowed the viewer to enter into a virtual world, filled with bright colors and concealed symmetries. If it was a scientific instrument (as the name implied), it was an instrument of some faerie science, a science of beauty. It partook of the potential of mirrors to create other worlds, to open up new infinite spaces. The forms were reminiscent of magical mandalas, and viewers often compared the hypnotic effect of looking through a shifting kaleidoscope to that of listening to music.


IF we examine the various objects of art which have exercised the skill and ingenuity of man, we shall find that they derive all their beauty from the symmetry of their form, and that one work of art excels another in proportion as it exhibits a more perfect development of this principle of beauty. Even the forms of animal, vegetable, and mineral bodies, derive their beauty from the same source... (Brewster chapter 20)


Brewster’s conception of beauty was grounded in neoclassicism. Symmetry and geometric order were key ideas in this. Beyond that, he assumed that a science of beauty was possible, that universal principles of beauty could be discovered. In The Kaleidoscope (a book on the optical theory behind the construction of his invention) he gives a theory of color harmony and repeatedly emphasizes the importance of carefully constructed devices that don’t allow the slightest imperfection in symmetry.
He conceived of the kaleidoscope as a labor saving device for artists, an automation of part of the creative process:


When we consider, that in this busy island thousands of individuals are wholly occupied with the composition of symmetrical designs, and that there is scarcely any profession into which these designs do not enter as a necessary part, so as to employ a portion of the time of every artist, we shall not hesitate in admitting, that an instrument must have no small degree of utility which abridges the labour of so many individuals. If we reflect further on the nature of the designs which are thus composed, and on the methods which must be employed in their composition, the Kaleidoscope will assume the character of the highest class of machinery, which improves at the same time that it abridges the exertions of individuals. There are few machines, indeed, which rise higher above the operations of human skill. It will create, in a single hour, what a thousand artists could not invent in the course of a year; and while it works with such unexampled rapidity, it works also with a corresponding beauty and precision. (Brewster chapter 20)


Things did not turn out quite as Brewster expected. Our use of machines to automate work previously done by artists has modified our concept of beauty. What used to take a great deal of skill and time could be done immediately and without effort by a mechanical process. This led to society valuing designs of rigid perfect symmetry less. A similar effect occurred with the invention of photography. Because of the ease of obtaining a perfectly accurate likeness, abstract and nonrepresentational art became more highly valued by the art world.


The kaleidoscope is a prototype for many computer programs that attempt to generate new works of art. Each one follows the same pattern:
1. Hand-selected forms to be recombined. Brewster recommends buttons, bits of broken glass, a distant bonfire, dancers, etc... [pull more examples from his book]
2. Random or nearly random input. In the kaleidoscope, this comes from shaking the bits of glass.
3. Formal constraints. The kaleidoscope uses mirrors to impose symmetry.


For example, a Markov poetry generator takes a set of words (preselected for the intended effect, such as all words used in works by a given author) recombine them randomly, but imposing constraints of use frequency patterns. Fractal generators use slightly more sophisticated symmetry constraints on the randomness. Similar examples can be found for music, such as David Cope’s EMI program. [include example output from each of these]


While all of these hold some interest in the beginning, after a short time newly produced works fail to add anything new to the already formed impression. Instead of learning individual works, our brains pick up on the pattern that underlies all of the output. Although at first it seemed that the machine was being creative, it later becomes apparent that a store of creativity injected, as it were, during the creation of the program, has merely been allowed to leak out slowly.
In Zen and the Art of Motorcycle Maintenance, Pirsig identifies two kinds of beauty: classical beauty and romantic beauty. [quote from Z&AMM here] Both are evident in these kaleidoscopic machines: the hand selected elements are romantically beautiful, beautiful in how they present themselves to the senses. The formal constraints are classically beautiful in how they appeal to the intellect.
It is comparatively simple to set up a system of rules and generate new images. It is much more difficult to choose a set of rules that will produce images that are aesthetically pleasing. In order to do the latter, we need to have some theory of beauty or interest. The attempt to mechanize requires that we understand; but the attempt to understand beauty transforms it. There is essentially a paradox here: creativity must continually be pushing the boundaries of what is new. Simply being new is not enough, however; to be considered creative it must be both new and beautiful. Any static conception of beauty must quickly become inadequate.
The problem becomes, then, how to make a machine that grows in ability over time, that is not limited by the initial choices made by the author of the program. In the next chapter [about Charles Darwin and Samuel Butler] we’ll look at how scientist came to understand how the creation of new forms could arise from the action of natural laws and immediately began to apply the concept to the development of creative machines.

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