Archimedean property

Let x and y be positive elements of a linearly ordered group G.
Then there exists a natural number nN such that nx>y.


Proof

Let x,yR.
Without loss of generality, choose x=1.

Suppose for the sake of contradiction that there is no nN such that 1n>y.
Then ny for all nN.
So y a supremum in N.

Since (y1) not a supremum in N, there exists some m>(y1) in N.
Since mN, (m+1)N.
However, (m+1)>y,
so y not a supremum in N (a contradiction).

reductio ad absurdum, QED


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