Due to the founder Kazimierz Twardowski, the requirement for clarity of philosophical style was one of the important features of the Lvov-Warsaw School. Yet, there was no widely accepted definition of clarity. In addition, the members disagreed on the issue of whether or not an unclear philosophical text is a sign of an unclearly thinking author. Certain members, e.g. Jan Łukasiewicz and Stanisław Leśniewski, adopted radical positions on this question and rejected all unclear philosophical texts. On the contrary, other members of the School mentioned that this position is too radical and contains several drawbacks. Among those members was Seweryna Łuszczewska-Romahnowa. On the one hand, she was aware of the importance of a clear style in philosophy and pedagogy and saw the request for clarity as one of the great contributions of the Lvov-Warsaw School to Polish philosophy. On the other hand, she stressed that swift discarding of obscure texts can do more harm than good. She argued that in philosophy (as well as in science) even unclearly formulated theories can produce valuable results. Seweryna Łuszczewska-Romahnowa discussed clarity on several occasions. My talk will focus on two of them, her discussion of clarity in Kazimierz Twardowski’s work and the paper 'Ambiguity in the language of science' published in Jerzy Pelc's collection 'Semiotics in Poland 1894–1969'.