Zygmunt Zawirski (1882-1948), an eminent and original Polish philosopher, belonged to the Lwow-Warsaw School (LWS) which left an indelible trace in logic, semiotics and philosophy of science. LWS was founded in 1895 by K. Twardowski, a disciple of Brentano, in the spirit of clarity, realism and analytic philosophy. LWS was more than 25 years older than the Vienna Circle (VC). This belies, inter alia, the not infrequently repeated statement that LWS was one of the many centres initiated by VC.