4. The common law rules relating to the unenforceability of penalties were derived from equitable principles determining the availability of relief in Chancery. Like all rules with true equitable foundations, they are concerned with substance rather than form. It would, for example, have been out of accord with equity's concern with substance for the availability of equitable relief against the enforcement of a performance bond (i.e. a money bond subject to conditional defeasance) to have depended upon whether it was possible to identify some implied contractual warranty of which the failure to perform or pay constituted a technical breach of contract on the part of the plaintiff. In fact, of course, equity observed no such limitation upon its jurisdiction to grant relief. It granted relief against the enforcement of such a bond by a common law action in debt regardless of whether the failure to bring about or prevent the event which precluded fulfilment of the condition of defeasance constituted a breach of contract at common law. Indeed, the equitable jurisdiction to grant such relief preceded the evolution of general common law notions of liability for breach of contract which occurred with the development of the action in assumpsit. Nor, in my view, did equity ever commit itself to what would, as Lord Denning pointed out in Bridge (at p.629), have been the "absurd paradox" that "it (would) grant relief to a man who breaks his contract but (would) penalise the man who keeps it". The reasons why such a paradox would be unacceptable to equity transcend the fundamental notions of justice to which Lord Denning referred (ibid.). They go to the very basis of equitable jurisdiction. Equity followed and built upon the common law, adding its remedies by way of enforcement of the common law in some cases and granting its relief against the harshness of the operation of the common law in others. It was not, however, subversive of the common law. It would have been contrary to the underlying thesis of the equitable jurisdiction to prevent unconscionable advantage being taken of the harshness of the common law to have made the existence of legal fault in the plaintiff, as distinct from legal liability, a prerequisite of entitlement to relief or to have made the contumacy of the plaintiff's conduct giving rise to legal liability a ground for equitable relief against the liability. A fortiori, it would have been unreasonable for the common law itself, in withdrawing its remedies to enforce what equity regarded as a penalty, to have added a limitation that common law unenforceability did not extend to any case where the person burdened by the penalty was innocent of common law fault in the form of breach of contract. It is true that one can point to judicial statements, including some recent statements of high authority, which support the contrary view that a contractual clause will not be unenforceable as a penalty unless it provides for payment upon breach of contractual duty (see, in particular, Tool Metal Manufacturing Co., Ltd. v. Tungsten Electric Co., Ltd. [1955] UKHL 5; (1955) 1 WLR 761, at p 767; [1955] UKHL 5; (1955) 2 All ER 657, at p 662; Export Credits Guarantee Department v. Universal Oil Products Co. (1983) 1 WLR 399, at pp 402-404; (1983) 2 All ER 205, at pp 223-224). Such broad statements appear to me, however, to have generally been made in a context where the grounds for declining to hold that a penalty was involved are properly to be seen as more narrowly confined: e.g., that the alleged penalty represented part of the agreed royalty payments for a non-exclusive licence under letters patent (Tool Metal Manufacturing); that the relevant contractual liability was pursuant to an indemnity agreement and corresponded with the loss incurred (Export Credits Guarantee Department); or, in a highly debatable area, that the alleged penalty was the price of a right or option to terminate exercisable by the party liable to make the payment (see, e.g., Associated Distributors, Ltd. v. Hall (1938) 2 KB 83; Lombank, Ltd. v. Kennedy and Whitelaw (1961) N.ILR 192, at pp 214-215; Bridge, at pp 613-614; but cf. Bridge, at pp 631 and 633; the dissenting judgment of Lord MacDermott L.C.J. in Lombank, at pp.206-209 and the comments of G.H.L. Fridman in (1963) 26 MLR, 198). I do not see any of those general statements as binding this Court. For my part, for the reasons given above, I am not prepared to accept them as correctly stating the position either in equity or at common law. As I have indicated, the restriction of equitable relief or common law unenforceability to the case where it is possible to identify a technical breach of contract on the part of the party claiming relief or unenforceability would, in my view, be contrary to historical fact, general principle and basic common sense.