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by pcmonk 3705 days ago
{A,B,C} is of greater cardinality than {A,B}. However, the argument that "a rule works for finite numbers, so it must work for infinite numbers" is clearly false.

For a your mapping, see: http://math.stackexchange.com/questions/512397/is-there-a-si...

1 comments

The distance between 0 and 1 is smaller than the distance between 0 and 2. The number of points between 0 and 1 is larger than the number of rational numbers.
> The distance between 0 and 1 is smaller than the distance between 0 and 2.

This is correct. However, the number of real-valued points between 0 and 1 is the same as the number of real-valued points between 0 and 2.

> The number of points between 0 and 1 is larger than the number of rational numbers.

This is also true because there are uncountably many real-valued points between 0 and 1 and countably many rational numbers.