Abstract
In this paper a concept of infinity is described which extrapolates themeasuring properties of number rather thancounting aspects (which lead to cardinal number theory).
Infinite measuring numbers are part of a coherent number system extending the real numbers, including both infinitely large and infinitely small quantities. A suitable extension is the superreal number system described here; an alternative extension is the hyperreal number field used in non-standard analysis which is also mentioned.
Various theorems are proved in careful detail to illustrate that certain properties of infinity which might be considered ‘false’ in a cardinal sense are ‘true’ in a measuring sense. Thus cardinal infinity is now only one of a choice of possible extensions of the number concept to the infinite case. It is therefore inappropriate to judge the ‘correctness’ of intuitions of infinity within a cardinal framework alone, especially those intuitions which relate to measurement rather than one-one correspondence.
The same comments apply in general to the analysis of naive intuitions within an extrapolated formal framework.
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Tall, D. The notion of infinite measuring number and its relevance in the intuition of infinity. Educ Stud Math 11, 271–284 (1980). https://doi.org/10.1007/BF00697740
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DOI: https://doi.org/10.1007/BF00697740