This collection of essays has its origins in recent courses and seminars at the University of Pisa on some logical, epistemological and ontological questions that, at the turn of the twentieth century, inspired the philosophical reflections of various authors on the problem of logical form, reflections which were fundamental in the history of analytic philosophy. The essays are authored by some of the people that took part in this research and they aim to further explore the expressive and analytic potential of logical forms in various directions.