In my opinion, when all of the relevant factors are weighed up, and, in particular, when regard is had to the fact that the moral obligation is just as likely to be honoured in the breach as in the observance, they do provide reason, or to use the language of the statute, constitute good cause shown, not for no allowance of interest, but for an allowance at a moderate rate rather than at a commercial rate, on damages for pre-trial gratuitous care. I consider this approach, although if not compelled by, to be consistent with the unanimous decision of this Court (Mason CJ, Brennan, Deane, Dawson, Toohey, Gaudron and McHugh JJ) in MBP (SA) Pty Ltd v Gogic[96]. There the Court held that interest on damages for non-economic loss sustained before trial, should not be calculated at current interest rates or at the real rate of interest which would have been available to the plaintiff in the relevant period, but on a rate which represents the difference between a rate for secure investments and the rate of inflation. Their Honours thought that the rate at the time of that decision should be fixed at four percent, acknowledging, in doing so, that their approach was necessarily an arbitrary one. Their Honours said that a plaintiff is awarded interest because he or she has been "deprived of the use of his or her money, not because he or she has forgone investment opportunities"[97]. I do not overlook that there was one significant difference in MBP (SA) Pty Ltd v Gogic. The damages in question there were for pre-trial pain and suffering, which fell to be assessed in the currency of the time of trial, whereas here, the damages for pre-trial gratuitous care were calculated by reference to the actual market charges, from time to time of the gratuitous care. But I do not think that is a reason for adopting a commercial rate of interest in this case. The Full Court of the Federal Court, in this case, was alive to this difference, but did not think that it provided reason for an award of interest at commercial rates[98]. Foster J made these points[99]: