
 The ChurchTuring Thesis 
  Turing did not show that his machines can solve any problem that can be solved "by instructions, explicitly stated rules, or procedures", nor did he prove that the universal Turing machine "can compute any function that any computer, with any architecture, can compute". 
  Turing introduces his machines with the intention of providing an idealised description of a certain human activity, the tedious one of numerical computation, which until the advent of automatic computing machines was the occupation of many thousands of people in business, government, and research establishments. 
  Copeland, B.J. ‘Turing's Omachines, Penrose, Searle, and the Brain’. 
 plato.stanford.edu /entries/churchturing (4930 words) 
