Really? I think the reasons for the requirements of evidence are justified in civil matters just as they are in criminal.
We cannot have a situation where men always have no defence because of a lack of requirement of evidence.
In a criminal case, if the defendant remains silent then it is up to the prosecution to present enough evidence.
In a civil case, any argument made by the plaintiff that is not rejected or corrected can be accepted as true.
Of course, legal systems vary, but in general there is no right to remain silent during a civil case.