Public Announcement Logic (PAL) models knowledge update as world elimination, with the well‑known property that truthful announcements commute: learning p then q yields the same epistemic state as learning q then p. This commutativity is typically treated as a harmless algebraic convenience. I argue that it encodes a substantive philosophical assumption: that epistemic justification is independent of the order in which information is acquired. To make this hidden commitment visible, I introduce
