W'riiinr/s. — The published works of Hamilton embrace the. lectures on logic and on metaph3^sics ; an edition of Kc'il, never completed; an edition of the works of Du- g ilil Stewart ; and a volume ai Dkcussions on Philosophy iiud Literature, Education and University Reform (1852 ; 2il edit, enlarged, 18.j3; reprinted by Harper and Broth- ers, X. York). There is little evidence of any taste for literature, properly so called, in the volume. " The only css.iy connected even remotely with polite letters is thai on the authorship of the KpistoliB Ohscurorum Virorum, which is, in some respects, his m'ost curious contribu- tion to periodical literature. A wide chasm separates this from the instructive andentcil.iininu papers On the Jfeiudut ions of Medicine, mid on M<ith, iii,iii<:< not Philos- ophy. Both of these readily cousorL witli the laborious and learned investigation of the history, condition, ob- jects, and possible ameliorations of university educa- tion. The remainder of the "Discussions" is' devoted to logic and metaphysics. The former science is illus- trated by the essay on Lor/ic. contributed to the Edin- burr/h Review in April, 1833; and that on Sylloyism, its kindi, canons, notations, etc., contained in the appentlix. The pL'culiar views of the author are further expounded in the Prospectus of an Essay on the A'ew Anali/tic of Eoyical Forms, and in the Prize Essay of Thomas Spen- cer Hnyaes on the same subject, to which should be add- ed the appendix to the lectures on logic.
Tlic principal metaphysiea! p ipersln the Discussions are tho.^e on The Philosophy „f/hr ComUtioned; on The Philosophy of Pn-cplion, au.l On Idndism.^yiih the at)- pendix On the Condition.': nf/hr ThinLuhl,'. In the cdi-
>rial labors on i;eiil, lieside; L'idali
nianv important notes elu- rectifying, .leveloping, or altering the state- ments ni the text, which merit carefid consideration should be specially stn.licd Note A, On the PhiU.mhi, of Common iiense ; Note 1'., On Presmldlir, mid /,;,„■<'- sentafire Knowledyo ; and Note 1), hi.-/;,,,/;,,,, „///„ fri- miry anl Secondary Qualities of li„dii. which has an inti.nate relation to the theory of immediate or prcsent- ative pt-ncplion.
Philosophy.— ha^ic, metaphysics, and ethics are com- prised un.ler the general designation of |)hilosophv. ihe last of these divisions is mitouched by Sir William
Hamilton. In the other two he has pushed his inqui- ries far beyond any of his British contemporaries, and with much more brilliant success. In both he evinced signal acuteness ; in both he rendered good service : and in both he deemed himself an inventor and reformer, and not merely an innovator.
The character of his metaphysical doctrine is mani- fested by the designation which he bestowed upon it — The Philosophy of the Conditioned. It is critical ni its procedure ; it is mainly negative in its results. In these respects it resembles the philosophy of Kant, to which it approximates in many of its developments. It is a crusade against all theories reposing on the absolute and the unconditioned. It sets out with affirming the es- sential relativity of all knowledge; it concludes with the restriction of philosophy to the determination of the conditions of thought. In this there is nothing new but the mode of exposition. It was a familiar aphorism of the schoolmen, founded upon the teachings of Aristo- tle, that all thought was bounded by the limits of the thinking mind — " omne perceptum est secundum inodum percipieiitis" — " onme scitum est in sciente secundum mo- dum scientis" — '^species cogniti est in cor/noscente." From this position Hamilton deduces the invalidity of all con- ceptions pretending to be absolute, and hence denies the possibility of any positive conception of the infinite. Herein he merely repeats Aristotle, but with less mod- eration in his doctrine. This thesis has been violentlj' opposed, and usually misapprehended. It was assailed by Calderwood, Philosophy of the Infinite, who confounds the negation of the Infinite in thought with the nega- tion of the infinity of God. It has been acceiited and applied by Mansel to theology in his Li mils uf i;, /if/ions Thouyhf. The next step is to a purely iiei;ati\e exijo- sition of causahty, as resulting from "mental unixitence" to conceive an absolute commencement. Sir William recognises that this interpretation conflicts with the idea of a great First Cause, and he propounds a very ingeni- ous apology for his doctrine. He similarly follows out his fundamental tenet to other applications, and arrives uniformly at negative conclusions.
The tenet, however, is not presented as an axiom, luit receives interpretation, if not demonstration. It is the inevitable consequence of the dualism of our knowledge — a thesis contained in Aristotle. Every act of con- sciousness "gives a knowledge of the ego in relation and contrast to the non-ego, and a knowledge of the non- ego in relation and contrast to the ego. The ego and non-ego are thus given, in an original synthesis, as con- joined in the unity of knowledge, and in an original antithesis, as opposed in the contrariety of existence." This " natural dualism" is accepted by professor Ferrier as the beginning of an antagonistic scheme of philoso- phy. With Hamilton it is made to rest upon the basis of immediate perception, and thus he is led to the affir- mation of direct or presentative perception in opposition to the older theory of indirect or representative percep- tion. This brings him into accordance with the school of Keid — though Keid and his school woidd scarcely have understood, and certainly could not have appreci- ated his delicate distinctions; and it must be acknowl- edged that it is a coarse and materialistic conception of species, images, and impressions which requires any deadly opposition between presentative and representa- tive perception. To one cultivating such divisions and differences, the treatise of Roger Bacon, De Multiplica- tione Specierum— the most marvellous result of mediae- val science— would be utterly unintelligible.