A High Court judge has thrown out two brothers' challenge to a £200,000 mortgage arrangement after they tried to claim there was no such thing as money.
Mr Justice Horner rejected a "bold" claim by Greg and Stuart Foster that there was no money, only currency exchanges.
He described their case as "a full frontal attack on the present financial and legal system".
The pair launched an appeal over being ordered to hand over possession of a house at Wellington Square in Belfast to the Bank of Scotland.
Proceedings were issued against them after they fell behind on repaying a £198,000 mortgage to buy the property.
Earlier this year the bank reached a new agreement with the brothers where they would pay £1,400 a month to cover ongoing instalments and the arrears.
However, the Fosters claimed in court they had a case which would allow them to escape from having to repay the principal sum and interest.
Setting out reasons for confirming the original order made against them, the judge said such a result would be surprising.
"The appellants would retain the benefit of the transaction, namely the property, but not be subject to any detriment such as having to pay for it," he said.
"In fact, the appellants' defence amounts to a full frontal attack on the present financial and legal system."
In a reference to monetary exchange rate systems, Mr Justice Horner added: "Indeed, they make the bold claim that following the abolition of the Gold Standard and the making of the Bretton Woods agreement, that there is now no such thing as money, only currency exchanges."
All grounds of challenge by the brothers were dismissed for having no legal or factual basis, including a contention that they were both the creditors and the debtors.
They claimed the debt was owed by SF and GF, who are men, while Greg and Stuart of the family Foster are legal persons and creditors.
"I am afraid that I was unable to follow their novel proposition for which no legal authority was offered," Mr Justice Horner said.
He added: "They have reached an agreement with the bank and it is difficult to understand why the appellants in those circumstances decided to spend hard earned money running an appeal without any obvious merit.
"For whatever reason they have decided to make a root and branch attack on the law of mortgages which, on reflection, they may feel was ill-advised."