To help Calian construct his argument, we can fill in the blanks as follows:
Any positive number raised to the power 1 is equal to itself. Written as an equation, this means that $$ b^1 = b $$ for any positive base. This equation is equivalent to the logarithmic equation $$ \log_b(b) = 1 $$.
Therefore, it must be true that log_b(b) = 1 for any positive base that is not equal to 1.