Another basic principle with respect to damages is that the plaintiff is to be compensated "not merely because his earning capacity has been diminished but because the diminution of his earning capacity is, or may be, productive of financial loss" [30] . It is that principle which may pose difficulty in some partnership cases. If, by reason of the nature of the partnership, an incapacitated partner has not suffered, and is not likely to suffer, any financial loss, the diminution of earning capacity will not sound in damages except, where appropriate, with respect to the loss of a chance. However, it must always be borne in mind that the task of the court is to assess damages for the loss of earning capacity. If it is productive of financial loss, then it is compensable. In Batt v Wilkinson [31] Derrington J, with whom the other members of the Court agreed, regarded a person's earning capacity as an asset provided it is used "in such a way that the deprivation of it causes him a loss of something which he [otherwise would] have had" [32] , no doubt applying the observation of Barwick CJ in Cullen v Trappell [33] : "The problem is to value the capital asset of the injured person, namely, his capacity to earn money." It is the loss of that asset, as it would have been utilised but for the injury which must be valued. I do not think that any of these principles can be doubted. It is their application to particular factual circumstances which gives the impression of differing approaches. In some cases the circumstances require assessment on the basis of the loss of profit from a partnership. There are cases where it is appropriate to measure the loss by the share of the partner in the cost of the replacement labour. In other cases it is appropriate to measure the loss by the total cost of replacing that labour. The approach in each case depends upon the circumstances. [34]
1. (1991) 172 CLR 60.
2. (1992) 60 SASR 481 at 491-492. See also at 494-497.
3. Graham v Baker (1961) 106 CLR 340 at 347; see also Griffiths v Kerkemeyer (1977) 139 CLR 161 at 165, per Gibbs J.
4. [1983] 2 Qd R 619.
5. Batt [1983] 2 Qd R 619 at 623.
6. (1980) 146 CLR 1 at 7.
7. On appeal the Full Court of South Australia (Bollen, Mohr and Millhouse JJ) affirmed his Honour's reasons and decision (Cole v Ellis (unreported; 13 May 1993)). Section 34(1) of the Wrongs Act 1936 SA confers a special benefit upon the spouse of an injured person. It provides: "Where a husband and wife are engaged in the conduct of a business, and either of them suffers an injury as a result of which his or her participation in the conduct of the business ceases or is impaired, the other spouse shall be entitled to recover from a person whose wrongful act, neglect or default caused the injury compensation for loss that he or she has suffered or continues to suffer by reason of the fact that the participation of his or her spouse in the conduct of the business has ceased or has been impaired."