added that it should never enforce unjust claims. The principle of utility confirmed that duties of justice had to be capable of being formulated as rules.
In the Introduction to the Principles, Kames added his views that it was better to have a single court with the power to administer both common law and equity (as in Scotland) and that the court of equity itself should follow rules. These were topics on which he had corresponded with the former Lord Chancellor of England, Lord Hardwicke, shortly before the publication of the first edition. Hardwicke disagreed on the first of these points, feeling that a union of the judicatures might allow a judge to alter the settled rules of property law at his discretion. Such an arbitrary power exercised in matters of property might then extend to matters of life and liberty. On the second point, Hardwicke admitted that there should be general rules which guided the court (such as those which related to trusts), yet he felt that the judge should not be absolutely and invariably bound by them. In his view, equity had grown in response to the luxuriant growth of fraud, and since fraud was infinite, the Lord Chancellor’s powers had to be flexible.41
If Lord Hardwicke was sceptical about some of Kames’s views, the Chief Justice of the King’s Bench, Lord Mansfield, was enthusiastic. After the publication of the first edition of the work, he wrote to Kames,
I read ev’ry thing yr L[ordshi]p writes with great Satisfaction. The best of our Judges are delighted with some of yr Law Pieces. You have taught Men to trace Law to its true noble Sources: Philosophy & History. Your Principles of Equity are very ingenious; but the Opposition of Equity to Law as now administered in England by different Courts, is not to be learnt from anything yet in Print & is not deducible from Reason. It can
[print edition page xxiv]
only be explained positively & by Historical Deductions. I wish we had a Pen & Genius & Diligence like yr L[ordshi]ps to do it.42
Mansfield wrote to Kames again when the latter was preparing the second edition of the book. Reflecting on the work, the Chief Justice wrote,
I was not single in wishing, you had considered Principles of Equity, not in opposition to, but as one Ground of Law absolutely necessary in the administration of justice the same at all times & in all places. Non alia lex Romae, alia Athenis43 [ . . . ] To reduce principles of Equity into a System of Science, & to illustrate them by Examples from all times & Countrys is a lesson of Jurisprudence to the whole World; & worthy of your Ldsp. It equally suits the Parliament of Paris, the Court of Session, & the Courts in England whether called of law or Equity, but the plan of a distinct Court of Equity, upon natural or political Principles may embarrass the Subject; & any allusion to the Case in England, upon a supposed natural division of law and Equity into two Sciences can only lead to mistakes.44
Lord Mansfield was famously enthusiastic about introducing equitable principles into his court, and Kames’s admiration for him was shown by the letter to Mansfield at the start of the second edition.45 Although it cannot be denied that these two judges did not always agree even on some of the most important issues of their day—as can be seen from the contrary positions
[print edition page xxv]
they took on the question whether there was a common law right to literary property46—Kames did, in at least one respect, modify his argument in the Principles of Equity to take a position closer to Mansfield’s view. Between the first and second editions of the work, Kames modified the formulation of his argument concerning the principles behind the restitutionary actio negotiorum gestio.47 Where in the earlier edition he rooted the obligation in an implied contract, in the later edition he rooted it in a broader notion of justice.48 Soon after Kames had finished the first edition of the Principles, Mansfield decided the case of Moses v. Macferlan, in which he described the English restitutionary action of money had and received as “an equitable action, to recover back money, which ought not in justice to be kept.” In so deciding, he rejected an argument that the remedy could only be brought in a case where an express or implied contract could be found, holding instead that “the defendant be under an obligation, from the ties of natural justice, to refund; the law implies a debt, and gives this action, founded in the equity of the plaintiff’s case.”49 Kames did not mention this case in the Principles—nor any other case of Mansfield’s50—but it may be assumed that England’s chief justice would have approved of the modification.51
[print edition page xxvi]
When the Principles of Equity was first published in 1760, Kames sought to use the text as a vehicle to gain promotion to the High Court of Justiciary.52 But long after he had achieved his ambition to be a criminal judge, he continued to refine and revise a work which he clearly regarded as of considerable importance. In November 1777, he wrote to a friend,
I have been busy at my Principles of Equity for a new edition ever since I returned from the Circuit; and I have never laboured harder upon any subject. That book I always considered as my chief performance; and the advance of ten years of my life since the last publication made me doubtful whether I would be able to make any improvement. It delighted me to find my mental faculties still entire, even so much as to be able to detect several errors that had escaped in the former edition. You cannot conceive my satisfaction in detecting these errors myself, instead of having my reputation wounded by their being detected after my death.53
A Note to the Reader
The pagination of the third edition is indicated in the text with page numbers placed within angular brackets (<1>). Readers should bear in mind that the original work was published in two octavo volumes, and that the material of volume 2 commences at p. 243 below.
Kames’s own notes, as in the original, are indicated by asterisks, daggers, and other symbols or by the letter (a), while the editor’s annotations of Kames’s notes appear within brackets. The editor’s own notes are indicated by arabic numerals.
[print edition page xxvii]
A NOTE ON LEGAL SOURCES AND CITATIONS
Kames’s Principles of Equity is replete with a large range of technical terms from Scots, Roman, and English law. To assist the reader, I have appended my own glossary to the text of terms used (p. 543), to serve as an addition to Kames’s brief “Explanation of Some Scotch Law Terms Used in This Work” (p. 15). Some of the language of Scots law uses terms which might at first glance appear to bear no specific meaning, but which in fact have a particular legal connotation. The glossary and notes seek to explain them as simply as possible. Latin tags and phrases are in general translated in the body of the text, but the glossary also contains terms used repeatedly.
The work also makes extensive reference to Scottish and English statutes and case law and to Roman law. What follows is a brief introduction to the citation of this material.
Scottish Legislation
At the time when Kames was writing, the standard printed collection of statutes was that produced by Sir Thomas Murray of Glendook, the lord clerk register from 1677 to 1681.1 It was produced in a folio edition in 1681 and a two-volume duodecimo edition in 1682 (taking the statutes to 1681), and was subsequently supplemented by another volume taking the collection to 1707. The duodecimo edition was the one most commonly cited in courts. In Kames’s day, the method used to refer to statutes was
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by reference to the year and chapter number given in Glendook’s edition (and not by name).2 It is
