Perception links organic and communicative processes. It can be perceived as an organic Process, i.e. it can be reflexive; it can be communicated about linguistically.
With all this, perception quite effectively excludes attribution as action and documents the status of selections as experience with a certainty sufficient for social purposes.
When Alter sees in Ego's presence that the jug is broken, neither of them can deny this contingent fact (although both experience it as contingent). Anyone who did so would draw attention to themselves and to the strangely divergent reasons for their actions.
On the related sanction mode of truth, namely exclusion from the circle of relevant co-experiencing subjects, see also Niklas Luhmann, "Selbststeuerung der Wissenschaft", in: ders. Soziologische Aufklärung 1, pp. 232-252 (233f.).
~
LUHMANN, Niklas, 2018. Systemtheorie der Gesellschaft. 2. Aufl. Berlin: Suhrkamp. ISBN 978-3-518-58705-8, p. 522–536 (527)