When historians look back on the 20th century and the decline of rationalism there are three events that they are likely use to organize their arguments for the end of scientific rationalism. The first is the development of quantum physics in the early part of this century. This issue, which was discussed earlier, led to a failure in scientific reductionism and destroyed the myth that science leads to ultimate truth. The development of quantum physics suggested that if you study a phenomenon long enough and hard enough, you might eventually come up with a new phenomenon even more inexplicable than the one you started out with.
The second event that will mark the end of the age of scientific rationalism is the defeat of the chess master Kasperov by the chess-playing machine Big Blue. And the third is the development of the World Wide Web. These three unlikely bedfellows are notable events in three significant trends that came together at the end of the 20th century to challenge some very fundamental beliefs that dominated western thinking for nearly five hundred years.
The camera was invented in the early 1800's and improved until the late 1800's when it became possible to take some pretty fair pictures. This new technology had an unexpected impact on the world of art. No painter could paint a picture as realistic as a photograph. So instead, the world of art said that realism wasn't important anymore. As this century began, we saw a host of new non-realistic art forms - cubism, dadaism, and surrealism - to name a few. The art world simply refocused its attention on things that a camera could not possibly do.
I use the defeat of Kasperov by Big Blue to mark the point at which computers became better at purely logical reasoning than humans. Human will respond by devaluing purely rational reasoning and refocus on kinds of reasoning that machines cannot do. It is anybody's guess as to how this will manifest, but my guess is that narrative reasoning and more emotionally based reasoning will be two of the responses.
Marshall McLuhan made the observation that the modern age of rationalism began with the invention of the printing press. Although, I doubt that this was an original observation, his reasoning was as follows. The printed medium forces the author to create disembodied arguments. Assumptions must be clearly articulated and reasons must be developed according to agreed upon rules. The reader cannot see the writer as he makes his arguments. Hence a lot of body language and facial expressions are lost. Further, the writer does not know his reader so any contextual or culturally based statements are risky. So in this sense, printed media led to more rational abstract thinking.
This perception of reasoning as being abstract and formal was further reinforced by the physical layout of the book. Words flowed from right to left, top to bottom, start to finish in a linear fashion. Multilevel or associative thinking could not be easily represented in this medium. Hence, over centuries as books became more widely available people began to view knowledge as rational, linear and abstract.
McLuhan also predicted that in the near future we would depart from this linear view of knowledge and begin to view knowledge in a more association framework as a multilevel web. He predicted new media in which knowledge would be represented using associative links. These links would allow a reader to jump from one idea to the next following their interests rather than the current linear media in which you can only view knowledge in the linear form to which the author reduced it.
This associative organization of knowledge is realized through hypertext and the first instantiation of large-scale associative knowledge is the current instance of the World Wide Web.
Having been brought up on books, we still have at least one foot in the linear view of knowledge camp. However, I would challenge that linear view by asking how often you have read all the way to the bottom of a web page without jumping to another page via a hyperlink. I would also ask if you have any trouble reading a book (other than a bestseller) from start to finish without hopping around. Kids growing up today are finding increasingly more of their information on the World Wide Web and are unknowingly adopting a view of knowledge as associative rather than linear. Just as the printing press ushered in the age of rationalism by presenting knowledge in a linear format, the World Wide Web will usher out the age of rationalism by presenting knowledge in an associative organization that will dominate epistemology for the next several centuries. As the 20th century and the second millennium come to an end, so will many familiar aspects of our lives. But thinking about the future keeps it from descending upon us too rapidly. Perhaps with some understanding of the forces in play we can face the future with confidence and direction rather than reeling in the face of future shock.
