Collections of sayings by philosophers and other bums are known as gnomologia – the idea being that they contain gnomic wisdom. These things exercised quite a bit of influence in antiquity.
One of the most famous collections of these is the Corpus Parisinum, so called because it is preserved in a massive manuscript (Ms. Paris graecus 1168) in the French National Library. It’s never been published, but it’s a central witness if you are trying to trace the history of a saying.
Well, it has now been edited! Dennis Searby has made a critical edition, with English translation, and Dimitri Gutas supplied a preface. I only wonder how I can get a look at a copy!
PS: There’s a table of contents here. One section (CP2) is pagan prophecies of the coming of Christ which didn’t make it into Maximus the Confessor. Dr Searby kindly sent me his intro to that section. The book is 1,000 pages, in two volumes, and looks like a treasure trove of valuable information.