before his time, is as much at variance with it as with any system that has been or ever can be broached on this subject.

As it will naturally fall in our way, at a future period of this discussion, to prove that our' ideas of power, active power, cause and effect may be derived from sensation and reflection, notwithstanding all that Dr. Reid and Mr. Hume have alleged to the contrary; and to show in what manner we arrive at the very important conclusion that every effect must have a cause, we dismiss the subject at present with remarking that the doctrines before stated as held by Mr. Hume, not only lead by inevitable consequence to atheism, but tend also to invalidate, and utterly to destroy, the force of the method of reasoning from induction, upon which all natural and experimental science is founded. "Supposing," says he," that the production of any one object by another, in any one instance, implies a power, and that this power is connected with the effect, we have no reason to infer that the same power still exists, from the appearance of the same sensible qualities. The appeal to past experience decides nothing; and at the very utmost can only prove, that that very object which produced any other, was at that very instant endowed with such a power, but can never prove that the same power must continue in the same object or collection of sensible qualities, much less that a like power is always conjoined to such sensible qualities. Thus," he concludes, "not only our reason fails us, in the discovery of the intimate connection, between causes and effects, but even after experience has informed us of their constant conjunction, 'tis impossible for us to satisfy ourselves by our reason why we should extend that experience beyond those particular instances which have fallen under our observation."

Thus, while with one hand, he would strike away the foundation upon which rests the proof of the existence of God, with the other he would overthrow the certainty of all

those sciences which consist, to use the language of Lord Bacon, in the interpretation of nature. All those sciences rest the certainty of their principles upon the ground of the stability of the constitution, and order of nature, and upon the uniformity and permanence of her laws; while Mr. Hume informs us that we have no reason to draw any inference from our own experience concerning the past or future. If this part of Mr. Hume's doctrine be true, we have no reason to conclude, because we have ascertained by a just induction that the united influence of the Sun and Moon occasions the ebbing and flowing of the tides to-day, that the same influence will produce that result to-morrow; because bodies now gravitate towards the earth, and the Planets towards the Sun, they will do so in future; in a word, because the Sun rises and sets to-day, and has always risen and set every twenty-four hours, since the Creation, it will rise and set to-morrow. Into such extravagancies and absurdities are men driven by the wanton spirit of scepticism. And yet this frivolous, and flimsy disquisition has been dignified with the title of profound reasoning, and acute metaphysicks. It forms a part of the task we have assigned ourselves to detect its fallacy, and exhibit the force and certainty of that part of our knowledge which rests upon experience or the inductive method of reasoning. We proceed, therefore, without further delay to the opinions of the remaining authors upon the subject of cause and effect.

CHAPTER V.

The opinions of other authors upon Cause and Effect.

Dr. Priestley, in speaking upon the subject of cause and effect, says, “a cause cannot be defined to be any thing but such previous circumstances as are constantly followed by a certain effect, the constancy of the results making us conclude that there must be a sufficient reason in the nature of the things why it should be produced in those circumstances." If by the expression, sufficient reason in the nature of the thing, be meant, as no doubt is meant, a power or efficiency in the cause to produce such results, we see no room for objection against this definition, but that it is couched in language rather inaccurate, when previous circumstances are placed in the same category with thing or cause, and that it does not furnish an example in which that author has expressed himself with his usual perspicuity and precision of style.

Mr. Hume's doctrine appears to have shed a baneful influence upon the Scottish school of metaphysicks, most of the writers of that school discovering in their productions some tincture of his opinions. Whether it be that Dr. Reid, from frequent perusal of the works of that celebrated sceptick, and from that admiration of his genius which he takes frequent opportunities to display, even while combatting his errors, was at first drawn insensibly into the vortex of that influence which the principles of Mr. Hume evidently obtained in his native country; or whether the Dr. in his earlier productions, had not as yet, (as he acknowledges to have been the case in reference to the immaterialism of Bishop Berkeley) seen those ulterior consequences that result from them, certain it is, that in his treatise upon the human mind, the

first and most crude of his publications, he has not only adopted some of the opinions but the very language of Mr. Hume, relative to cause and effect.* “What we call natural causes," says he, "might with more propriety be called natural signs; and what we call effects, the things signified. The causes have no proper efficiency or causality, as far as we know: and all that we can certainly affirm, is, that nature hath established a constant conjunction between them and the things called their effects, and hath given to mankind a disposition to observe their connections, to confide in their continuance, and to make use of them for the improvement of our knowledge and increase of our power." Again he expresses himself to the same purport. "For effects and causes in the operations of nature mean nothing but signs and the things signified by them; we perceive no proper causality or efficiency in any natural cause, but only a connection established by the course of nature between it and what is called its effect." This, it will be perceived is precisely the language of Mr. Hume, and as far as the structure and operations of the physical world are concerned, to all intents and purposes, his doctrine. But how are we to reconcile these views of this matter to the following passage, as well as others which will be afterwards adduced. "The chain of natural causes," says Dr. Reid," has not unfitly been compared to a chain hanging down from Heaven; a link that is discovered supports the link below it, but it must itself be supported; and that which supports it must itself be supported, until we come to the first link which is supported by the throne of the Almighty. For every natural cause must have a cause until we ascend to the first cause which is uncaused and operates not by necessity, but by will." Professor Stewart has remarked an inconsistency between this and * Chap. 5. sect. third. Inquiry concerning the human mind. † See chap. 6. sect 24. Inquiry concerning the human mind. See Essay 2. chap. 6. vol. 1. Intellectual and active powers.