Kernrechtsfrage
Whether the borrowers could rely on Art. 8 CC to demand proof regarding the treatment of 17,440 francs in completion costs as own funds.
Extrahierter Entscheid
Art. 8 CC was not applicable because the cantonal court's finding rested on evidentiary appreciation, not on a failure of proof; the complaint was therefore inadmissible.
Extrahierte Begründung
The provision does not regulate how a judge forms conviction and cannot be used to attack factual findings or evidentiary assessment.