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From: WM <wolfgang.mueckenheim@tha.de>
Newsgroups: sci.math
Subject: Re: The reality of sets, on a scale of 1 to 10 [Was: The
 non-existence of "dark numbers"]
Date: Wed, 2 Apr 2025 16:20:42 +0200
Organization: A noiseless patient Spider
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On 28.03.2025 01:59, Moebius wrote:
> Am 27.03.2025 um 21:07 schrieb WM:
> 
>> For finite sets cardinality is a meaningful notion expressing the 
>> number of elements.
> For infinite sets it is a "generalisation" of the notion "number of 
> elements".
> 
> Hint: "In mathematics, the cardinality of a set is the number of its 
> elements.

This is wrong because an element can be added without changing the 
cardinality.

Regards, WM