# Canter's method

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Can anybody tell me the Canter Method of proving that certain sets are infinite? It is called as "Diagonal Method".

2. ### Zurtex

1,123

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Hey thanks, Zurtex! But from the first link, it does not become clear why it is called "Diagonal Method". Also, can you explain the link between first proof and second proof, please? Also, please tell me how to construct a bijection between Rationals & Reals.

4. ### shmoe

1,994
See the wiipedia article, step 5 in the proof singles out the 'diagonal' terms of the list. I only count one proof in the links he gave.

There isn't one. The diagonal argument shows the reals are uncountable while the rationals are countable.