and the contribution is more enriched than the adopter; for what, in another, is but a passing reflection, seen in a faint light, isolated and fruitless, often rises, in the hands of Sir William Hamilton, to the rank of a great, permanent, and luminous principle, receives its appropriate place in the order of truths to which it belongs, and proves, in many instances, a centre of radiation over a wide expanse of the field of human knowledge.

The present volume may also appear to some disadvantage on account of the length of time which has elapsed between its composition and its publication. Other writings, particularly the Dissertations appended to Reid's Works,1 and part of the new matter in the Discussions, though earlier in point of publication, contain later and more mature phases of the Author's thought, on some of the questions discussed in the following pages. Much that would have been new to English readers twenty years ago, has, subsequently, in a great measure by the instrumentality of the Author himself, become well known; and the familiar expositions designed for the oral instruction of beginners in philosophy, have been eclipsed by those profounder reflections which have been published for the deliberate study of the philosophical world at large.

But, when all these deductions have been made, the work before us will still remain a noble monument of the Author's philosophical genius and learning. In many respects, indeed, it is qualified to become more popular than any of his other publications. The very necessity which the Author was under, of adapting his observations, in some degree, to the needs and attainments of his hearers, has also fitted them for the instruction and gratification of a wide circle of general readers, who would have less relish for the severer style in which some of his later thoughts are conveyed. The present Lectures,

1 The foot-notes to Reid were, for the most part, written nearly contemporaneously with the present Lectures.

if in depth and exactness of thought they are, for the most part, not equal to the Dissertations on Reid, or to some portions of the Discussions, possess attractions of their own, which will probably recommend them to a more numerous class of admirers; while they retain, in no small degree, the ample learning and philosophical acumen which are identified with the Author's previous reputation.

Apart, however, from considerations of their intrinsic value, these Lectures possess a high academical and historical interest. For twenty years, from 1836 to 1856, -the Courses of Logic and Metaphysics were the means through which Sir William Hamilton sought to discipline and imbue with his philosophical opinions, the numerous youth who gathered from Scotland and other countries to his class-room; and while, by these prelections, the Author supplemented, developed, and moulded the National Philosophy, leaving thereon the ineffaceable impress of his genius and learning, he, at the same time and by the same means, exercised over the intellects and feelings of his pupils an influence which, for depth, intensity, and elevation, was certainly never surpassed by that of any philosophical instructor. Among his pupils there are not a few who, having lived for a season under the constraining power of his intellect, and been led to reflect on those great questions regarding the character, origin, and bounds of human knowledge, which his teachings stirred and quickened, bear the memory of their beloved and revered Instructor inseparably blended with what is highest in their present intellectual life, as well as in their practical aims and aspirations.

The Editors, in offering these Lectures to the public, are, therefore, encouraged to express their belief, that they will not be found unworthy of the illustrious name which they bear. In the discharge of their own duties as annotators, the Editors have thought it due to the fame of the Author, to leave his opinions to be judged entirely by their own. merits, without the accompaniment of criticisms, concurrent or dis

sentient.

For the same reason, they have abstained from noticing

such criticisms as have appeared on those portions of the work which have already been published in other forms.

Their own annotations

are, for the most part, confined to occasional explanations and verifications of the numerous references and allusions scattered through the text. The notes fall, as will be observed, into three classes:

I. Original; notes printed from the manuscript of the present Lectures. These appear without any distinctive mark. Mere Jottings or Memoranda by the Author, made on the manuscript, are generally marked as such. To these are also added a few Oral Interpolations of the Author, made in the course of reading the Lectures, which have been recovered from the note-books of students.

These are

II. Supplied; notes extracted or compiled by the Editors from the Author's Common Place Book and fragmentary papers. enclosed in square brackets, and are without signature.

III. Editorial; notes added by the Editors. These always bear the signature "ED." When added as supplementary to the original or supplied notes, they are generally enclosed in square brackets, besides having the usual signature.

The Editors have been at pains to trace and examine the notes of the first and second classes with much care; and have succeeded in discovering the authorities referred to, with very few and insignificant exceptions. The Editors trust that the Original and Supplied Notes may prove of service to students of Philosophy, as indications of sources of philosophical opinions, which, in many cases, are but little, if at all, known in this country.

The Appendix embraces a few papers, chiefly fragmentary, which appeared to the Editors to be deserving of publication. Several of these are fragments of discussions which the Author had written with

a view to the Memoir of Mr. Dugald Stewart, on the editorship of whose works he was engaged at the period of his death. They thus possess the melancholy interest which attaches to the latest of his compositions. To these philosophical fragments have been added a few papers on physiological subjects. These consist of an extract from the Author's Lectures on Phrenology, and communications made by him to various medical publications. Apart from the value of their results, these physiological investigations serve to exhibit, in a department of inquiry foreign to the class of subjects with which the mind of the Author was ordinarily occupied, that habit of careful, accurate, and unsparing research, by which Sir William Hamilton was so eminently characterized.