How Much Does a Theorem Cost?

Euclid is phenomenally famous as the author of the Elements. Indeed, no mathematical book has ever been read, edited, praised or criticized more than his magnum opus. However, very little is known about his life. For centuries, scholars have tried to discover new evidence with not much success. Thus, a reasonable question arises: 'Is there anything left to say?' This paper provides evidence that the answer to this question is positive. But what is crucial here is that this particular evidence is revealed, not via a discovery of some new material, but as a result of a revolutionary practice: the digitalization of the ancient Greek literature. As a case study, this paper focuses on the extant anecdotes associated with Euclid; one recorded by the philosopher Proclus Lycaeus and the other by the anthologist Joannes Stobaeus. In an attempt to shed some light on the matter of the origins of the latter anecdote, I draw parallels between this and a hitherto largely ignored Pythagorean symbol. This approach, I argue, can offer valuable insight into the textual tradition of the symbol and the conceptual background of the anecdote in question.