bioramani
The discussion amongst some of us interested was whether the decimal system had universal (literally) applicability or if it was because humans had ten fingers. After all there were some systems 12 based and twenty based.
Very interesting. We are at an advantage now , thanks to computers we are accustomed to binary , hexadecimal and octal systems too. I think we have a love for the decimal simply because we have ten fingers as you say.
Though I think the binary system would be more universal than any other system. As we know it needs only two symbols. And a being would start to use it after it had learned to construct a number system using the concepts of 'presence' and 'absence' of a single entity. To illustrate , we humans take absence of current as '0' and presence of it as '1', roughly speaking. ( However we don't seem to have made use of the concept of absence/presence while coming across decimal system. Else we would have had a system with a base of eleven. Zero corresponding to absence of finger, one-ten corresponding to the ten fingers . 😐 It is interesting to note that Romans did not have 0).
In Real Analysis , mathematicians use another abstract concept to create the numbers , that of a set. A set as we know is defined on the concept of 'membership'. Each set is defined purely by what members it has.
Entire number system can be created using only the null set.
A set having no members is the null set - Ï
. This is used to denote zero.
Then the set containing the null set i.e {Ï} is used to denote 1. ( {Ï} is diffeent from Ï)
Set containing the previous two sets i.e {Ï,{Ï}} is used to denote 2.
And so on. Thus we have constructed zero and the positive natural numbers simply out of the concept of 'membership'. I will provide links to constructions of other types of numbers :-
<a href="https://en.wikipedia.org/wiki/Integer#Construction" target="_blank" rel="nofollow noopener noreferrer">Integer Construction</a>
<a href="https://en.wikipedia.org/wiki/Rational_number#Formal_construction" target="_blank" rel="nofollow noopener noreferrer">Rational Number Formal Construction</a>
Construction of real numbers
Each construction makes use of the more basic concept constructed earlier. But point is just out of the null set we are able to construct conceptually the entire number line.