Philosophy 1050: Introduction to Philosophy Week 13: AI in the Real World and Review

The Turing Test ► A judge is connected to two subjects by teletype machine ► One of the subjects is a machine and the other is a person: the judge doesn’t know which is which ► If the machine can fool the judge into believing it is a person, it is actually thinking.

The Turing Test ► “I believe that in about fifty years' time it will be possible to programme computers, with a storage capacity of about 10 9, to make them play the imitation game so well that an average interrogator will not have more than 70 per cent chance of making the right identification after five minutes of questioning.” (p. 4) ► Do we agree with Turing? If a computer can pass the Turing test 70% of the time, is it actually thinking?

Computer Thinking: Objections 1) The Theological Objection: “Thinking is a function of man’s immortal soul. God has given an immortal soul to every man and woman, but not to any other animal or to machines. Hence no animal or machine can think.” (p. 5) Response: 1) If God can create bodies and attach souls to them, he could also attach souls to computers 2) Theological arguments are unsatisfactory for establishing scientific conclusions

Computer Thinking: Objections 2) The “Heads in the Sand” Objection: “The consequences of machines thinking would be too dreadful. Let’s hope and believe that they cannot do so.” (p. 6) Response: This is not really an argument at all, but just an appeal for consolation.

Computer Thinking: Objections 4) The Argument from Consciousness: “No machine could feel (and not merely artificially signal...) pleasure at its successes, grief when its valves fuse, be warmed by flattery, be made miserable by its mistakes, be charmed by sex, be angry or depressed when it cannot get what it wants.” (Geoffery Jefferson, 1949 (P. 6)) Response: If it is impossible to know that a machine is really conscious judging from its responses, then it is impossible to know whether any other person is really conscious as well. If the Turing test could not show that a computer is really thinking, then it is impossible for me to show that anyone else (other than myself) is really thinking.

Computer Thinking: Objections 5) Arguments from Various Disabilities: No computer could ever do X (where X is, e.g. “Be kind, resourceful, beautiful, friendly, have initiative, have a sense of humour, tell right from wrong, make mistakes, fall in love, enjoy strawberries and cream, make some one fall in love with it, learn from experience, use words properly, be the subject of its own thought, have as much diversity of behaviour as a man, do something really new.” (p. 8) Response: Various, but all of these seem to be based on a bad extrapolation from what we have seen before. Some of the computers we have seen cannot do these things, but that is no reason to think we could not eventually build a computer that can.

Computer Thinking: Objections 6) Lady Lovelace’s Objection: Computers only do what they are programmed to do, so it is impossible for a computer ever to learn something new or do something unexpected Response: Computers do “new” and surprising things all the time. It is also easily possible for us to set up a mechanism whereby a computer can modify its own program, and thereby can be said to have “learned.”

The Loebner Prize ► Every year, philanthropist Hugh Loebner sponsors a “real-life” Turing Test ► He offers $100,000 to any computer program that can successfully convince a panel of judges that it is “more human” than at least one human subject ► Every year, $2,000 is offered for the program judged “most human”.

The Loebner Prize ► Which of the transcripts seemed “most human”? Which did not seem “human” at all? Why?

The Loebner Prize: Things to Look For ► Ambiguity. Many words in English have multiple meanings. For example: “He put a check on the board” (here ‘check’ can mean either a monetary instrument, or a mark). ► ‘Canned’ responses. Many of the responses that a computer might give seem “automatic” or inappropriate to the situation (how can you tell?) ► Jokes and puns. It is difficult for computers to understand jokes or puns that depend on the difference between literal and metaphoric meaning (why?)

Review: A Philosophical Symposium ► In our conversation this semester, we have tried to figure out what we ourselves think in dialogue with great thinkers from the tradition of philosophy. ► An important question for all of these thinkers has always been: “What are we, ourselves?” That is: “What defines a human being and makes us the humans that we are?”

Review: A Philosophical Symposium ► Let’s see what the various philosophers would say about each of the following statements:

► 1) After we die, there is a part of us that lives on in some form. ► 2) The existence of an immaterial soul cannot be proven, one way or the other. ► 3) There is a level of reality that goes beyond what we can sense with our five senses. ► 4) Modern science can explain everything about our consciousness and behavior.