it, analysing, as we go along, the opinions of the successive writers.

The world had been entertained by philosophers, and especially by Des Cartes, with an opinion that many of the ideas which we possess were the original impress of the Creator, and had existed in our minds since the commencement of our life, being brought along with us into the world. Some men conceived, after Plato, that those ideas had been acquired in a pre-existent state, and were the fruits of our experience while there; but others, disclaiming this hypothesis, adopted the opinion that they were impressed on us at our creation, and formed, as it were, part of the constitution of our minds. To confute this opinion was a principal object of Mr. Locke in his admirable work on the Understanding. That eminent philosopher, subjecting our ideas to a strict and close examination, analysed the materials from which they are compounded, and shewed that they are all derived from two sources, namely, sensation and reflection, under the latter of which he designed to comprehend our knowledge of the natural operations of all the powers of our minds. In prosecuting this object, however, like a candid lover of truth, he assumed our ideas to be such as they are, and endeavoured to reconcile them one by one to his views of their origin. If the origin of one of these ideas could not have been accounted for consistently with his

views, he felt that those views must be abandoned in so far as they disclaimed the hypothesis of innate ideas. For had it been but one idea, that one must have been accounted innate. Mr. Locke's work is an excellent piece of inductive reasoning. Its venerable author would have rejected with disdain the thought of first setting up the general principle that we had no innate ideas, the whole being obtained by sensation and reflection, and then pretending to tell men, by this test, what ideas they had and what they had not; but he assumed our ideas to be such as they are felt and known to be, and, accounting for the origin of each, ascended to this general conclusion.

Mr. Hume, however, with his usual acuteness and penetration, has seen fit to reverse Mr. Locke's steps. The proposition that we had no ideas but by sensation and reflection, had become established in men's minds, and Mr. Hume knew that it might long retain its influence, although the reasoning on which it was based should be slyly invalidated. It is probable that even his own mind was the dupe of this illusion; but, be this as it may, he employed this proposition to overthrow the very principles on which it is itself founded. "All our ideas," says he,*" are nothing but copies of our impressions, or, in other words, it is impossible

Hume's Essays, vol. ii. Inquiry concerning the Human Understanding, section vii.

for us to think of anything which we have not antecedently felt, either by our external or internal senses. To be fully acquainted, therefore, with the idea of power or necessary connection, let us examine its impression; and in order to find the impression with greater certainty, let us search for it in all the sources from which it may possibly be derived. When we look about us towards external objects and consider the operation of causes, we are never able in a single instance to discover any power or necessary connection-any quality which binds the effect to the cause, and renders the one an infallible consequence of the other. We only find that the one does actually in fact follow the other. The impulse of one billiard ball is attended with motion in the second. This is the whole that appears to the outward senses. The mind feels no sentiment or inward impression from this succession of objects; consequently there is not, in any single particular instance of cause and effect, any thing which can suggest the idea of power or necessary connection.”

"It appears," he proceeds, in the second part of the same essay, "that in single instances of the operation of bodies, we never can, by our utmost scrutiny, discover any thing but one event following another, without being able to comprehend any force or power by which the cause operates, or any connection between it and its supposed effect. The same difficulty occurs in

contemplating the operations of mind on body, where we observe the motion of the latter to follow upon the volition of the former, but are not able to observe or conceive the tie which binds together the motion and volition, or the energy by which the mind produces this effect. The authority of the will over its own faculties and ideas is not a whit more comprehensible; so that, upon the whole, there appears not, throughout all nature, any one instance of connection which is conceivable by us. All events seem entirely loose and separate. One event follows another, but we never can observe any tie between them. They seem conjoined, but never connected. But as we can have no idea of any thing which never appeared to our outward sense or inward sentiment, the necessary conclusion seems to be, that we have no idea of connection or power at all, and that these words are absolutely without any meaning when employed either in philosophical reasonings or common life.

"But there still remains one method of avoiding this conclusion, and one source which we have not yet examined. When any natural object or event is presented, it is impossible for us, by any sagacity or penetration, to discover, or even conjecture, without experience, what event will result from it, or to carry our foresight beyond that object, which is immediately present to the memory and senses. Even after one instance or experiment, where we

have observed a particular event to follow upon another, we are not entitled to form a general rule, or foretell what will happen in like cases; it being justly esteemed an unpardonable temerity to judge of the whole course of nature from one single experiment, however accurate or certain.* But when one particular species of events has always, in all instances, been conjoined with another, we make no longer any scruple of foretelling the one, upon the appearance of the other, and of employing that reasoning which can alone assure us of any matter of fact or existence. We then call the one object Cause, and the other Effect. We suppose that there is some connection between them some power in the one by which it infallibly produces the other, and operates with the greatest certainty and strongest necessity.

"It appears, then, that this idea of a necessary connection among events, arises from a number of similar instances which occur, of the constant conjunction of these events, nor can that idea ever be suggested by one of these instances, surveyed in all possible lights and positions. But there is nothing in a number of instances, different from every single instance, which is supposed to be exactly similar; except only, that, after a repeti

* This statement is altogether erroneous. One experiment, where the circumstances are fully known, is always esteemed perfectly decisive and satisfactory.