The method of testing ideas in practice and relying on the ones that prove success- ful (for that is what 'induction' is) is not unjustified. That is an empirical statement. The method does not have a 'justification'—if by a justification is meant a proof from eternal and formal principles that justifies reliance on the method. But then, nothing does—not even, in my opinion, pure mathematics and formal logic. Practice is primary.