By presumption, the law assigns a certain meaning to human behaviour. This is independent of whether it really corresponds to the will of the contracting parties in the concrete case. The presumption thus focuses on the existence or non-existence of the facts, irrespective of the actual facts. A distinction can be made between rebuttable presumptions (with for proof of the contrary) and irrefutable presumptions (fictions). In the case of an irrefutable presumption, no proof to the contrary is admissible.
German: Vermutung (837)
Source: LK-Lötscher, 11.05.2020