It is a widely accepted believe that logic systems should be free of contradictions. In reality, however, we are always faced with contradictions and even seemingly unsolvable contradictions which we call paradoxes. How can we handle them? Logic in Praxis and Theory Computer programs consist of algorithms. Algorithms are instructions on how and in what order an input is to be processed. Algorithms are nothing more than applied logic and a programmer is a practising logician. But logic is a broad field. In a very narrow sense, logic is a part of mathematics; in a broad sense, logic is everything