Given the fact that consciousness is a biological phenomenon, and given the "agreed propositions" of Darwinian evolution by natural selection, one may wonder why we haven't been able to produce any plausible evolutionary explanation for human cognition. Most books and articles that have been written about evolution of human cognition are largely storytelling, as evolutionary biologist Richard Lewontin suggests. Even Daniel Dennett, an American philosopher and a staunch advocate of Darwinian theory, admits that “Unlike most explanations in science, evolutionary explanations are essentially narratives,....” ... Historically, we are permanently in this disadvantageous position of not being able to rewind all the processes and all the modifications that had been made during the aeon of evolutionary time to see what happened. And also, in the beginning of life, "nobody was around to see what happened," as Richard Dawkins, British biologist points out.
After a disappointment in the mechanistic view of the mind in Galilean terms, a new version of that view has emerged from Alan Turing, Hungarian-American Mathematician, who introduced the idea of Artificial Intelligence (AI). He suggested in his paper, "Computing Machinery and Intelligence," that if a computer engaged a conversation with a human being, and the human being didn't realize that he was talking to a computer, that computer would be considered an intelligent device. Although Turing didn't claim that such a computer would be conscious, Dennett and some other functionalists claim that in such a situation, that computer is conscious. Turing's test provoked a wide range of pro-and-con debates over whether a computer would be capable of doing whatever a human could do or not.
After carefully investigating human thought and language, Descartes began doubting the idea that our thought processing is a result of mechanistic interaction among the parts of the body. He wrote, "The fact that [machines] do better than we do, doesn't prove that they are endowed with mind."
Despite the progress in understanding the origin of life on the Earth, the question of how the evolution from organic molecules to a self-replicating cell happened remains unanswered. And more astonishing than that, how did cells manage to gather themselves into chunks of intelligent matter, namely brain? How can few million sensory nerve fibers enable us to think, to understand, and to decide?