In fact, before the 1920s and 1930s no serious philosophical reflections on mathematics and logic existed in Polish science. Naturally, this does not mean that philosophical concepts concerning mathematics and logic, developed in interwar Poland—being the main topic of this book—were formulated in an intellectual vacuum and that earlier there had not been any reflections on mathematics and logic in Poland. Therefore, let us mention six figures that exerted certain influences—each made a completely different impact—on the further development of the concepts in question. These figures are Jan Śniadecki and Józef Maria Hoene-Wroński working at the turn of the eighteenth and nineteenth centuries as well as Henryk Struve, Władysław Biegański, Samuel Dickstein and Edward Stamm at the turn of the nineteenth and twentieth centuries, i.e. closer to the interwar period.