Dateline: May 23, 2001

Nanotechnology can be qualitatively understood as an approach to alchemy that is based on the current model of matter. For more than 2000 years, the Aristotelian model of matter went relatively unquestioned in the western world. In this model, matter consisted of four elements: earth, air, fire and water. The variety of materials in existence was explained by the idea that the ratios of these elements within a material determined the form that the matter took. Based on this theory, the idea that one might rearrange the elements to create a desired material naturally followed. The arts of alchemy were early attempts to achieve this goal. In the last centuries, alchemy became more of a philosophy while its techniques were divided between chemistry, nuclear physics and various other disciplines.

In the 18th and 19th century, a far more accurate and productive model of the elements was finally developed. Lavoisier started the change with the discovery of a material that he called "oxygen" and began to arrange the other known elements into four groups. Dalton then proposed the importance of atomic masses, after which Mendeleyev noticed a pattern that resulted in the periodic table of the elements. Early in the 20th century, Pauling provided an accurate model of how these elements bond together to form molecules. These molecules can in turn interact by means of weak interactions. The chemical bonds and molecular interactions seem to be flawlessly explained by quantum mechanics, making our model of matter relatively complete.

With the new model being far more complex than the original one, the alchemist's goal of arbitrarily rearranging the elements became too confusing to pursue directly, until recently. During the last century, physicists and mathematicians have been ironing out the kinks in quantum mechanics. Chemists have found numerous ways to synthesize and characterize a plethora of molecules. Biologists have made enormous progress in understanding the molecular mechanisms and weak interactions that allow life to function. Meanwhile, the industrial revolution has provided us with machines, computers and other tools enabling further progress.