Use the concept of addition to show that 9 > 3.
It is easy to say that 3+1=4, 4+1=5...8+1=9, therefore 9>3.
Mathematically, this "proof" is erroneous because the concept of addition is based on the order/sequence of numbers, which in turn is based on the number line.
For the above proof to be valid, we need to first prove that 9>8, 8>7, ...4>3, which goes back to the number line.