‘Can Computers think?’ ‘Is time travel into the past possible?’ Philosophy

Philosophy touches on some of the fundamental questions which affect human lives. We would like to illustrate to you two such ideas, one relating to the nature of the mind and the other relating to the nature of time.

The first question is whether computers can think. Imagine you try to find out by running an experiment. You place a human being and a computer behind a screen, in separate rooms, and then you invite people to ask them questions. You must make sure that the people you test have no way of identifying whether they are talking to a computer or to a person. You can ask any question you like. Now imagine that after many hours and many questions, you are unable to decide whether the answer came from the machine or from the human. Should you then conclude that the machine can think in the same way as the human? And should you say that humans are just thinking machines?

The second question is whether time travel into the past is possible. You will all have seen films involving time travel. You may have heard about or even studied the book The Time Traveller by H. G. Wells, which was published in 1895. But is it possible that humans could build time machines to visit the past? The problem is that it would involve strange dilemmas. Here is one of them: Imagine a person, called Abe, who dislikes his father Zac so much that he wishes that Zac had never been born. So he builds a time machine and travels back to a time of his grandparents’ youth, equipped with a gun. When Abe arrives in, say, 1952 he spots his grandfather (Zac’s father) courting his grandmother and shoots him in cold blood. His wish has come true! His father Zac will never be born. The trouble is that Abe will never be born either so how can he travel into the past to prevent his father’s birth? Are there any ways out of this dilemma?