Understand that time is a spiral, each concentric circle forms a Wheel, so there are many Wheels in the Aurbis. (When the timeline is interrupted or broken, it's because pieces from neighboring Wheels have collided. This event resemblesthe unison of two bubbles of infinite mass. What happens when two worlds meet, which are so similar, a man can be a god in one, but a netchiman in the other? The apotheosis of historical figures, or even simultaneous sightings of a man, are due from such marriages.) Consider the center of the Aurbis the ultimate Tower. Ur Tower was constructed, based on the assumption there's an ultimate Tower, in the House of Sithis, uniting Aurbis and Mundus.
This is important, because Mundus is bursting with people - everyone is a different perspective; different desires, different hopes, different truths. Could there be a divine center, beneath all this noise? He would need to be alive through all the worlds of Aurbis. The truly, common man. Can there be unison - a love so strong - to pull these fragments together, into one, Universal Self? An event-stream piercing all the swirls of Aurbis, written in the genealogy of one, True Man. The Psijic Order believe so. They must hope so, because they survived the Hist destruction of Tamriel. They are the eternal witness of what will happen, if the Man/Mer schism is not healed. Artaeum's rescue scheme would be miraculous rescue, indeed.
Ur Tower's exposed sheets allow access of the True Man, the Dragonborn of their Order's mythic genealogy, into the figure Lorkhan, divined from Sithis, made famous by their monomythism.