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Two-Pincher Gripper
                            way. Some people believe that the smartest machine, and even the human
                            brain, works according to two-valued logic. If that is true, our brains are
                            nothing more than massive sets of biological truth tables whose values
                            constantly shift as our thoughts wander.
                              See also BOOLEAN ALGEBRA.
                         TURING TEST
                            The Turing test is one method that has been used in an attempt to find
                            out if a machine can think. It was invented by logician Alan Turing.
                              The test is conducted by placing a male human (M), female human
                            (F), and questioner (Q) in three separate rooms. None of the people can
                            see the others. The rooms are soundproof, but each person has a video
                            display terminal. In this way, the people can communicate. The object: Q
                            must find out which person is male and which is female, on the basis of
                            questioning them. But M and F are not required to tell the truth. Both M
                            and F are told in advance that they may lie. The man is encouraged to lie
                            often, and to any extent he wants. It is the man’s job to mislead the ques-
                            tioner into a wrong conclusion. Obviously, this makes Q’s job difficult,
                            but the test is not complete until Q decides which room contains the man,
                            and which contains the woman.
                              Suppose this test is done 1000 times,and Q is right 480 times and wrong
                            520 times. What will happen if the man is replaced by a computer, pro-
                            grammed to lie occasionally as does the man? Will Q be right more often,
                            less often, or the same number of times as with the real man in the room?
                              If the man-computer has a low level of artificial intelligence (AI), then
                            according to Turing’s hypothesis, Q will be correct more often than when
                            a human male is at the terminal, say 700 times out of 1000. If the man-
                            computer has AI at a level comparable to that of a human male, Q should
                            be right about the same number of times as when the man was at the
                            terminal—say, correct 490 times and wrong 510 times. If the computer
                            has AI at a level higher than that of the human male, then Q ought to be
                            wrong most of the time—say, correct 400 times and mistaken 600 times.
                              The Turing test has not produced comprehensive results concerning
                            computers with levels of AI higher than the intelligence of a human being,
                            because no such computer has yet been developed. However, computers
                            have been devised with high-level AI relative to specialized skills or tasks,
                            such as board games. Powerful computers have proven equal to human
                            masters at the game of chess, for example.

                         TWO-PINCHER GRIPPER
                            One of the simplest types of robot gripper uses two tongs or pinchers.
                            Because of its construction, it is called a two-pincher gripper.




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