Retrocausality, or the incurrence of the future into a past event, is a rare phenomenon which can occur within the same or multiple layers of the space-time continuum. The future influencing the past in a four dimensional continuum can only be achieved by a) briefly passing through the five dimensional reality of Subexistence and b) by an act of retro-Weaving while present in Subexistence.
As knowledge about Subexistence and how to access is generally kept within the few, retrocausality and its broad effect on the fabric of time are poorly-documented at best. There are, however, some testimonies of Weavers accessing Subexistence (whether by intent or by accident) and they all classify retrocausality not only as “immoral” but “dangerous”.
The Guild of Seers, in particular, seems to vehemently oppose the act of messing about with the timeline under the claim that it has the potential to destabilize the very fabric of reality. Of course, their aversion towards changing time can also stem from a deep-seated fear of being wrong. After all, if a Seer witnesses an implacable version of the future, and that future is changed in retrospect, Seeing as “academic talent” could be getting the boot.