The following paper deals with the problematic category of authorship in ancient philosophical literature. Philosophers are divided into two groups: the first consist of non-writing protagonists (e. g. Socrates, Ammonius of Saccas), while the second category includes writing authors (e. g. Plato, Aristotle). Paper argues that with regard to their „historicity“, between these two groups of philosophers is no substantial difference. Philosophical texts were often written in co-authorship. Many students and later adherents passed their own doctrines off as teacherʼs originals. Moreover, due to the fact that the very texts were transcribed countless times, there is no certainty about original phrasing of the documents that came down to our mode...