Prove that either

**a)** this problem is solvable

or

**b)** this problem is unsolvable

The PROBLEM states that we must prove something or the the other which is contradict to the previous. This means that one of the statements (a or b) is false. The only possible situations are given by "a" and "b" (No other situation can occur). So if one is false the other is True. A truth is provable. Therefore this problem is solvable.