Kernrechtsfrage
Whether the cantonal court arbitrarily assessed the evidence regarding A.'s contractual status as joint debtor or surety.
Extrahierter Entscheid
The evidence did not compel the conclusion that the parties intended a suretyship; the finding that A. bound himself as joint debtor was not arbitrary.
Extrahierte Begründung
The witness statements and A.'s own declarations did not clearly show a different common intent; the challenged inferences from the documents and testimony were sustainable.