Until a few decades ago the opinion prevailed in England and in the United States, as also in continental Europe, that a contract is an agreement, although certain additional requirements were necessary to distinguish contract from other classes of agreement (see infra, para. 6). More recently, however, many leading American and English scholars have tended to substitute “promise” (or “aggregate of promises”) for “agreement”.

What characterizes the new view is not the mere use of the term “promise”: such use was widespread before and still continues among opponents of this view, and it is hard to deny that an obligatory contract is a promise or an aggregate of promises. The followers of the new view are distinguished by the fact that they prefer to define contract solely in terms of promise and sometimes even go so far as to reject agreement as an element of contract.

“I should have thought this result, in the language of one of your Lordships, ‘manifestly impossible’; but rules of law have to be tested in these days, and must survive the application of first principles.” Lord Atkin, in Banco de Portugal v. Waterlow & Sons, Ltd. [1932] A.C. 452, 486–87.

With the arrival upon the scene of the House of Lords' decision in Tomkinson v. First Pennsylvania Banking and Trust Co. [1961] A.C. 1007 it is now settled that whenever judicial occasion may arise to convert foreign into English money, the conversion should be performed in accordance with the rate of exchange prevailing on the day when the money first became due and was not paid. This “breach-date rate” is preferred to the rate at commencement of suit, to the rate during trial or at judgment, to the rate on the day of actual payment, and to any other possible rate. It is to be followed regardless of whether the shift in the exchange results in appreciation or in depreciation of English money vis-à-vis the foreign money in question, as also without regard to whether it is the creditor or the debtor who benefits therefrom. Conversion in accordance with this rate is also preferred to an adjustment of the rights of the parties on equitable lines, as by judicial compromise between creditor and debtor.

Four fundamental and inter-related points must be borne in mind when discussing existing or prospective legislation on the treatment of mentally-sick offenders:

First, the basic misconception in regard to the true nature of the issue of criminal insanity; secondly, the long-standing conflict between the legal and medical professions in regard to this issue, and the need to shift the centre of the conflict from the substantive to the procedural levels where considerable progress towards close cooperation has already taken place; thirdly, the inter-relationship of the procedural and substantive levels and the great power which the former is capable of wielding over the latter; and fourthly, the effects of the typical, traditional modes of procedure and trial techniques of individual countries on their existing laws and on future legislative progress.

The dual nature of the problem of the mentally-sick offender has been the source of much confusion. The substantive tests of criminal responsibility predicated on the mental condition of the accused at the time of the offence have been confused with the distinct problem of the modes of ascertaining his mental condition before, during or after criminal trial, and the setting up of machinery for disposal or treatment.