PHENOMENA OF DREAMING.

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without parallel in the history of the human faculties. All children believe that the earth is at rest; and that the sun and the fixed stars perform a diurnal revolution round it. They also believe that the place which they occupy on the surface is absolutely the uppermost, and that the inhabitants of the opposite surface must be suspended in an inverted position. Now of this universal, practical, and irresistible belief, all persons of education are easily disabused in speculation, though it influences their ordinary language, and continues, in fact, to be the habitual impression of their minds. In the same way, a Berkleian might admit the constant recurrence of the illusions of sense, although his speculative reason were sufficiently convinced of their fallacy.

The phenomena of Dreaming and of Delirium, however, appear to afford a sort of experimentum crucis, to demonstrate that a real external existence is not necessary to produce sensation and perception in the human. mind. Is it utterly absurd and ridiculous to mantain, that all the objects of our thoughts may be "such stuff as dreams are made of?" or that the uniformity of Nature gives us some reason to presume that the perceptions of maniacs and of rational men are manufactured, like their organs, out of the same materials? There is a species of insanity known among medical men by the epithet notional, in which, as well as in delirium tremens, there is frequently no general depravation of the reasoning and judging faculies, but where the disease consists entirely in the patient mistaking the objects of his thought or imagination for real and present existences. The error of his perceptions, in such cases, is only detected by comparing them with the perceptions of other people; and it is evident that he has just the same reason to impute error to them, as they can have individually for imputing it to him. The majority, indeed, necessarily carries the point, as to all practical conse. quences: But is there any absurdity in alleging that we can have no absolute or infallible assurance of that as to which the internal conviction of an individual must be

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ORIGIN OF PERCEPTION.

supported, and may be overruled by the testimony of his fellow-creatures?

Dr. Reid has himself admitted that "we might probably have been so made, as to have all the perceptions and sensations which we now have, without any impression on our bodily organs at all." But it is surely altogether as reasonable to say, that we might have had all those perceptions, without the aid or intervention of any material existence at all. Those perceptions, too, might still have been accompanied with a belief that would not have been less universal or irresistible for being utterly without a foundation in reality. In short, our perceptions can never afford any complete or irrefragable proof of the real existence of external things; because it is easy to conceive that we might have such perceptions without them. We do not know, therefore, with certainty, that our perceptions are ever produced by external objects; and in the cases to which we have just alluded, we actually find perception and its concomitant belief, where we do know with certainty that it is not produced by any external existence.

It has been said, however, that we have the same evidence for the existence of the material world, as for that of our own thoughts or conceptions; - as we have no reason for believing in the latter, but that we cannot help it; which is equally true of the former. Now, this appears to us to be very inaccurately argued. Whatever we doubt, and whatever we prove, we must plainly begin with consciousness. That alone is certain

all the rest is inference. Does Dr. Reid mean to assert, that our perception of external objects is not a necessary preliminary to any proof of their reality, or that our belief in their reality is not founded upon our consciousness of perceiving them? It is only our perceptions, then, and not the existence of their objects, which we cannot help believing; and it would be nearly as reasonable to say that we must take all our dreams for realities, because we cannot doubt that we dream, as it is to assert that we have the same evidence for the

IDEALISTS NEITHER MAD NOR WICKED.

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existence of an external world, as for the existence of the sensations by which it is suggested to our minds.

We dare not now venture farther into this subject; yet we cannot abandon it without observing, that the question is entirely a matter of philosophical and abstract speculation, and that by far the most reprehensible passages in Dr. Reid's writings, are those in which he has represented it as otherwise. When we consider, indeed, the exemplary candour, and temper, and modesty, with which this excellent man has conducted the whole of his speculations, we cannot help wondering that he should ever have forgotten himself so far as to descend to the vulgar raillery which he has addressed, instead of argument, to the abbettors of the Berkleian hypothesis. The old joke, of the sceptical philosophers running their noses against posts, tumbling into kennels, and being sent to madhouses, is repeated at least ten times in different parts of Dr. Reid's publications, and really seems to have been considered as an objection not less forcible than facetious. Yet Dr. Reid surely could not be ignorant that those who have questioned the reality of a material universe, never affected to have perceptions, ideas, and sensations, of a different nature from other people. The debate was merely about the origin of these sensations; and could not possibly affect the conduct or feelings of the individual. The sceptic, therefore, who has been taught by experience that certain perceptions are connected with unpleasant sensations, will avoid the occasions of them as carefully as those who look upon the object of their perceptions as external realities. Notions and sensations he cannot deny to exist; and this limited faith will regulate his conduct exactly in the same manner as the more extensive creed of his antagonists. We are persuaded that Mr. Stewart would reject the aid of such an argument for the existence of an external world.

The length to which these observations have extended, deters, us from prosecuting any farther our remarks on Dr. Reid's philosophy. The other points in which it appears to us that he has left his system vulnerable are,

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CAUSE AND EFFECT

LIBERTY AND NECESSITY.

his explanation of our idea of cause and effect, and his speculations on the question of liberty and necessity. In the former, we cannot help thinking that he has dogmatised, with a degree of confidence which is scarcely justified by the cogency of his arguments; and has endeavoured to draw ridicule on the reasoning of his antagonists, by illustrations that are utterly inapplicable. In the latter, also, he has made something more than a just use of the prejudices of men and the ambiguity of language; and has more than once been guilty, if we be not mistaken, of what, in a less respectable author, we should not have scrupled to call the most palpable sophistry. We are glad that our duty does not require us to enter into the discussion of this very perplexing controversy; though we may be permitted to remark, that it is somewhat extraordinary to find the dependence of human actions on Motives so positively denied by those very philosophers with whom the doctrine of Causation is of such high authority.

Memoirs of Dr. Joseph Priestley, to the year 1795, written by himself: With a continuation to the time of his decease, by his Son Joseph Priestley; and Observations on his Writings. BY THOMAS COOPER, President Judge of the Fourth District of Pennsylvania, and the Reverend WILLIAM CHRISTIE. pp. 481. London: 1805.

8vo.

DR. PRIESTLEY has written more, we believe, and on a greater variety of subjects, than any other English author; and probably believed, as his friend Mr. Cooper appears to do at this moment, that his several publications were destined to make an æra in the respective branches of speculation to which they bore reference. We are not exactly of that opinion: But we think Dr. Priestley a person of no common magnitude in the history of English literature; and have perused this miscellaneous volume with more interest than we have usually found in publications of the same description. The memoirs are written with great conciseness and simplicity, and present a very singular picture of that indefatigable activity, that bigotted vanity, that precipitation, cheerfulness, and sincerity, which made up the character of this restless philosopher. The observations annexed by Mr. Cooper are the work, we think, of a powerful, presumptious, and most untractable understanding. They are written in a defying, dogmatical, unaccomodating style; with much force of reasoning, in many places, but often with great rashness and arrogance; and occasionally with a cant of philosophism, and a tang of party politics, which communicate an air of vulgarity to the whole work, and irresistibly excite a smile at the expense of the