What is thinking?

As a philosophy major, this dialogue hit close to home for me. What is thinking? How do we know we are thinking? How do we know what we are thinking is the same or comparable to what others are thinking? How do I know that what I see as the color green is the same as what you see as the color green? All of these are classic metaphysical and epistemological philosophical questions.

After taking an intro level computer science class, I concluded that the real difference between human and machine is irrationality, error and emotions. Artificial Intelligence definitely pushes these limits, though. Computers can be programmed to mimic human behavior and thought to a surprising extent. In his book The Human Use of Human Beings published in 1950, theoretical mathematician Norbert Wiener points out that all nerves in the human body are in a binary state (on or off, zero or 1 - as in computer programs). The logical conclusion from this, given that human brains are made up entirely of nerves, would be that computers can indeed be programmed to think like humans. The limits to this are not yet clear, but I think the differences between "human thinking" and "computer thinking" will continue to narrow as long as humans choose to continue to develop more complex technology.

Here's an interesting article on a Stanford computer science professor who has spent his "entire life" thinking about the differences between computers and humans.