Re: Cantor Confusion

Virgil wrote:
In article <1159417542.425540.214160@xxxxxxxxxxxxxxxxxxxxxxxxxxx>,
cbrown@xxxxxxxxxxxxxxxxx wrote:
the_wign@xxxxxxxxx wrote:
1. Assume there is a list containing all the reals.
2. Show that a real can be defined/constructed from that list.
3. Show why the real from step 2 is not on the list.
4. Conclude that the premise is wrong because of the contradiction.

That is a proof by contradiction, which many constructionists object to.

No, they don't, presuming you mean constructivists. A direct constructivistic proof of ~A is a proof of contradiction from A. What one can't do constructively is to prove A by proving that ~A leads to a contradiction.

--
Aatu Koskensilta (aatu.koskensilta@xxxxxxxxx)

"Wovon man nicht sprechen kann, daruber muss man schweigen"
- Ludwig Wittgenstein, Tractatus Logico-Philosophicus
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