Man and the related humanoids are pattern-sensing creatures, time-binding animals. So it is of little surprise that they determined how to bind concepts into words, how to bind words back into concepts, and how to link these to the Tapestry that holds reality together. (Modern physicists would call this Tapestry "spacetime," but fantasy sages don't usually include spacetime in their worldken.)
The first humanoids to do this can be considered the first natural philosophers, as their conclusions arose from careful study of the natural world. Beyond the mere archival qualities of the sage, however, these were experiential, empirical philosophers. They go by many names, but players and game rulebooks typically call them druids.
The druids of Khaldun were the first to wrest the secrets of magic out of the land, the root from which the other magical traditions spring. (It makes sense when you think about it. They channel divine magic from the land like priests, but wrap their arcana in secrets and codes like wizards.) The druids were among the first to enumerate (and then, over the aeons, forget) the slow, green war. And in the Age Before Ages, they were the most powerful magic-users on the face of Khaldun.
They shaped the world.
Before the war between gods and Primordials, they created strange wonders, chief among which is the system of Moonpaths.that once connected the far-flung corners of the world. Available wherever moonlight shines, the Moonpaths were relatively stable shortcuts allowing nearly instantaneous travel among disparate locations. They usually connected between druidic sacred sites and other important places, allowing druids to meet and defend these strategic locations at a moments' notice.
But such magic was long ago. The gods and Primordials made war, the Tapestry changed, and the Moonpaths collapsed. Most that remain are broken, dangerous, and unstable, often appearing only at certain times or when summoned by ancient chants and blood rites.
Strangely, archaic records suggest that druids often met on Khaldun's moon, implying that it was not the lifeless ball of rock it currently is. But this may be poetic, as archaic records often claim many metaphorical things that are not true, like saying there were two moons.
(Of course, some of these things may be true. The Dark Powers of Ravenloft claim that the ancient elves hid thousands of years of history in the hopes of destroying a potent world-emperor. And while most sages blame the ancient war between thought and matter for catastrophes like the convergences, they were instead caused by this forgotten empire — meaning that all manner of history might be lost to time. Likewise, the Archfey Vance recently informed his subjects of a civilization on the Faerie reflection of the moon, so maybe there is something to the moon once having held life...)
