Deane J, in the same case, observed at 474:
"The jurisdiction of courts of equity to relieve against unconscionable dealing developed from the jurisdiction which the Court of Chancery assumed, at a very early period, to set aside transactions in which expectant heirs had dealt with their expectations without being adequately protected against the pressure put upon them by their poverty. The jurisdiction is long established as extending generally to circumstances in which (i) a party to a transaction was under a special disability in dealing with the other party with the consequence that there was an absence of any reasonable degree of equality between them and (ii) that disability was sufficiently evident to the stronger party to make it prima facie unfair or 'unconscientious' that he procure, or accept, the weaker party's assent to the impugned transaction in the circumstances in which he procured or accepted it. Where such circumstances are shown to have existed, an onus is cast upon the stronger party to show that the transaction was fair, just and reasonable: 'the burthen of shewing the fairness of the transaction is thrown on the person who seeks to obtain the benefit of the contract' (see per Lord Hatherley, O'Rorke v. Bolingbroke (1877) 2 App. Cas., at p. 823; Fry v. Lane (1888) 40 Ch.D. 312, at p. 322; Blomley v. Ryan (1956) 99 CLR 362, at pp. 428-429).
The equitable principles relating to relief against unconscionable dealing and the principles relating to undue influence are closely related. The two doctrines are, however, distinct. Undue influence, like common law duress, looks to the quality of the consent or assent of the weaker party (citations omitted). Unconscionable dealing looks to the conduct of the stronger party in attempting to enforce, or retain the benefit of, a dealing with a person under a special disability in circumstances where it is not consistent with equity or good conscience that he should do so. The adverse circumstances which may constitute a special disability for the purposes of the principles relating to relief against unconscionable dealing may take a wide variety of forms and are not susceptible to being comprehensively catalogued. In Blomley v. Ryan, Fullagar J. listed some examples of such disability: 'poverty or need of any kind, sickness, age, sex, infirmity of body or mind, drunkenness, illiteracy or lack of education, lack of assistance or explanation where assistance or explanation is necessary' As Fullagar J. remarked, the common characteristic of such adverse circumstances 'seems to be that they have the effect of placing one party at a serious disadvantage vis-a-vis the other'".
12 In Tanwar Enterprises Pty Ltd v Cauchi [2003] HCA 57; 77 ALJR 1853 the High Court discussed the concept of unconscionable conduct in a case involving a claim for equitable relief against forfeiture. In that context Gleeson CJ, McHugh, Gummow, Hayne and Heydon JJ in their joint judgment observed at [23] that the phrase "unconscionable conduct" tends to mislead in the several respects that are discussed in the succeeding paragraphs. By these proceedings the Plaintiff claims orders under the FTA in respect of unconscionable conduct engaged in by the First Defendant in the supply of services to various of her clients. Section 43 of the FTA is not confined to a consideration of the circumstances as they existed at the time of the formation of the contract but includes consideration of conduct that occurs during the course of the contract. In Holloway v Witham (1990) 21 NSWLR 70 Lee CJ at CL said at 74:
"But important though it be that the Act enables the Commissioner to make applications on behalf of consumers for compensation, the real virtue in the Act, in so far as it is aimed at unfair trading, is that it enable remedies available to consumers and/or the Commissioner which are dependent, not upon breach of contract by the trader, but upon proof of specific conduct on the part of the trader as defined in the Act. The fact that the trader may by reason of the conduct engaged in be in breach of the contract, is largely irrelevant to the pursuit of remedies provided by the Act and, equally, breach of contract by the consumer will not necessarily displace the right of the consumer to the remedies provided in respect of the conduct of the supplier. In Holt v Biroka Pty Ltd (1988) 13 NSWLR 629, Kearney J held that s 4(4) of the Act, in defining "conduct", produced the result that the conduct to be considered was the whole of the conduct related to the contractual bargain and its performance and I respectfully adopt that view - it plainly carries out the purpose of the Act."