irishda said:
Either way you don't get .999r=1
As for the fractions, I understand you need to know fractals in order to refute that one, but it's still refutable.
As with most mathematical proofs (particularly in mathematical induction), you presuppose that what you're trying to prove is true. Then, if it is true, it's all internally consistent; if it's not true, there is some contradiction which breaks the internal consistency.
In the proof using fractions, we are working under the assumption 1/3 = 0.333...
This is the key step. Most people do not question this step, because it is elementary. If you disagree with it, then we'll never agree.
If you are interested in other proofs, there's a geometric series proof here [http://www.purplemath.com/modules/howcan1.htm], though you'll only accept this one if you can accept that what we know about geometric series is correct.
As for refutability; these are not 'refutable' because they are facts, it doesn't matter how much you know about infinitives, transinfinitives or fractals, they remain true. Maybe some day we will discover we were wrong, but it hasn't happened yet, and I doubt that anybody here is going to be the person to disprove it (but hey, stranger things have happened).