Turing test on the machine's ability to render words as speech. If the evaluator cannot reliably tell the machine from the human, the machine is said to have passed the test. The test results do not depend on the machine's ability to give correct answers to questions, only how closely its answers resemble those a human would give. The test was introduced by Turing in his 1950 paper, "Computing Machinery and Intelligence", while working at the University of Manchester (Turing, 1950; p. 460). It opens with the words: "I propose to consider the question, 'Can machines think? Because "thinking" is difficult to
Turing degree same level of unsolvability; each Turing degree is a collection of Turing equivalent sets, so that two sets are in different Turing degrees exactly when they are not Turing equivalent. Furthermore, the Turing degrees are partially ordered so that if the Turing degree of a set "X" is less than the Turing degree of a set "Y" then any (noncomputable) procedure that correctly decides whether numbers are in "Y" can be effectively converted to a procedure that correctly decides whether numbers are in "X". It is in this sense that the Turing degree of a set corresponds to its level