"Tim Little" <tim@little-possums.net> wrote in message news:slrni1qrip.jrj.tim@soprano.little-possums.net... > On 2010-06-19, Peter Webb <webbfamily@DIESPAMDIEoptusnet.com.au> wrote: >> Take the list, determine the nth digit of the nth item, blah >> blah. Remember, just as in Cantor's proof, you have to provide the >> list first. > > You don't get to "take the list" to compute the diagonal, as the list > is an infinite object in contradiction to the requirement of "finite > algorithm" in the definition of "computable real". >
The anti-diagonal can be computed to any required degree of accuracy. There is an explicit construction for every digit in its decimal expansion. Try and tell me how it is uncomputable.