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Re: 2+2=4 ... How?
Posted:
Sep 27, 2012 2:15 PM


In article <5064948F.B2FF9E32@btinternet.com>, Frederick Williams <freddywilliams@btinternet.com> writes: >Madhur wrote:
>> The natural numbers that we use are said to be derived from what so called Peano's Axioms. While these axioms (listed below) give a method of building up counting numbers they do not define or construct basic arithmetic operations like addition, subtraction, multiplication, etc or basic comparisons like that of equality. My doubt is how exactly we reach the conclusion: 2+2=4? >> >> Peanoâs Axioms of Natural numbers (N) >> We assume that the set of all natural numbers has the following properties:
>> Notice that there is no mention of such things as addition or multiplication. How are these to be defined? > >Recursively: > >x + 1 = x
Did you possibly mean
x + 1 = x'
 Michael F. Stemper #include <Standard_Disclaimer> Life's too important to take seriously.



