Higher properties - such as truth, beauty or virtue - are prospective. There is no fixed rule or token by which we can recognise the true or the beautiful or the good: these are human ideals and not computable. Nor is there any kind of program or attitude which will enable any individual person or school to produce all truth or all beauty or all goodness: our highest goals are not to be exhausted by the logical working-out of any single system.Church's theorem is a metaphor for the first fact, the fact that no simple test can give Yes or No answers for important questions. And Godel's theorem is a metaphor for the second fact, the fact that no logical program can hope, even in the limit, to answer all the questions.
Rudy Rucker, Mind Tools
