III.

PART derstanding; and where the one is obscure, the other is uncertain; where the one fails, the other must fail also.

Of knowledge and Secondly, 'tis certain that this repetition of similar probability objects in similar situations, produces nothing new either

in these objects, or in any external body. For 'twill readily be allowed, that the several instances we have of the conjunction of resembling causes and effects, are in themselves entirely independent, and that the communication of motion, which I see result at present from the shock of two billiard balls, is totally distinct from that which I saw result from such an impulse a twelvemonth ago. These impulses have no influence on each other. They are entirely divided by time and place; and the one might have existed and communicated motion, though the other never had been in being.

There is, then, nothing new either discovered or produced in any objects by their constant conjunction, and by the uninterrupted resemblance of their relations of succession and contiguity. But 'tis from this resemblance, that the ideas of necessity, of power, and of efficacy, are derived. These ideas therefore represent not any thing, that does or can belong to the objects, which are constantly conjoined. This is an argument, which, in every view we can examine it, will be found perfectly unanswerable. Similar instances are still the first source of our idea of power or necessity; at the same time that they have no influence by their similarity either on each other, or on any external object, We must therefore turn ourselves to some other quarter to seek the origin of that idea.

Though the several resembling instances, which give rise to the idea of power, have no influence on

XIV.

Of

the idea of

connexion.

each other, and can never produce any new quality in SECT. the object, which can be the model of that idea, yet the observation of this resemblance produces a new impression in the mind, which is its real model. For after we have observed the resemblance in a sufficient number of necessary instances, we immediately feel a determination of the mind to pass from one object to its usual attendant, and to conceive it in a stronger light upon account of that relation. This determination is the only effect of the resemblance; and therefore must be the same with power or efficacy, whose idea is derived from the resemblance. The several instances of resembling conjunctions lead us into the notion of power and necessity. These instances are in themselves totally distinct from each other, and have no union but in the mind, which observes them, and collects their ideas. Necessity, then, is the effect of this observation, and as nothing but an internal impression of the mind, or a determination to carry our thoughts from one object to another. With out considering it in this view, we can never arrive at the most distant notion of it, or be able to attribute it either to external or internal objects, to spirit or body, to causes or effects.

The necessary connexion betwixt causes and ef fects is the foundation of our inference from one to the other. The foundation of our inference is the transi tion arising from the accustomed union. These are therefore the same.

The idea of necessity arises from some impression. There is no impression conveyed by our senses, which can give rise to that idea. It must, therefore, be derived from some internal impression, or impression of reflection. There is no internal impression which has any relation to the present business, but that propen

III.

Of

PART sity, which custom produces, to pass from an object to the idea of its usual attendant. This, therefore, is the essence of necessity. Upon the whole, necessity is knowledge and something that exists in the mind, not in objects; nor probability is it possible for us ever to form the most distant idea of it, considered as a quality in bodies. Either we have no idea of necessity, or necessity is nothing but that determination of the thought to pass from causes to effects, and from effects to causes, according to their experienced union.

Thus, as the necessity, which makes two times two equal to four, or three angles of a triangle equal to two right ones, lies only in the act of the understanding, by which we consider and compare these ideas; in like manner, the necessity of power, which unites causes and effects, lies in the determination of the mind to pass from the one to the other. The efficacy or energy of causes is neither placed in the causes themselves, nor in the Deity, nor in the concurrence of these two principles; but belongs entirely to the soul, which considers the union of two or more objects in all past instances. 'Tis here that the real power of causes is placed, along with their connexion and necessity.

I am sensible, that of all the paradoxes which I have had, or shall hereafter have occasion to advance in the course of this Treatise, the present one is the most violent, and that 'tis merely by dint of solid proof and reasoning I can ever hope it will have admission, and overcome the inveterate prejudices of mankind. Before we are reconciled to this doctrine, how often must we repeat to ourselves, that the simple view of any two objects or actions, however related, can never give us any idea of power, or of a connexion

:

XIV.

Of the idea of

connexion.

betwixt them that this idea arises from the repetition SECT. of their union: that the repetition neither discovers nor causes any thing in the objects, but has an influence only on the mind, by that customary transition it produces that this customary transition is therefore necessary the same with the power and necessity; which are consequently qualities of perceptions, not of objects, and are internally felt by the soul, and not perceived externally in bodies? There is commonly an astonishment attending every thing extraordinary; and this astonishment changes immediately into the highest degree of esteem or contempt, according as we approve or disapprove of the subject. I am much afraid, that though the foregoing reasoning appears to me the shortest and most decisive imaginable, yet, with the generality of readers, the bias of the mind will prevail, and give them a prejudice against the present doctrine.

This contrary bias is easily accounted for. 'Tis a common observation, that the mind has a great propensity to spread itself on external objects, and to conjoin with them any internal impressions which they occasion, and which always make their appearance at the same time that these objects discover themselves to the senses. Thus, as certain sounds and smells are always found to attend certain visible objects, we naturally imagine a conjunction, even in place, betwixt the objects and qualities, though the qualities be of such a nature as to admit of no such conjunction, and really exist no where. But of this more fully hereafter.* Meanwhile, 'tis sufficient to observe, that the same propensity is the reason why we suppose neces

*Part IV. sect. 5.

III.

Of

PART sity and power to lie in the objects we consider, not in our mind, that considers them; notwithstanding it is not possible for us to form the most distant idea of that quality, when it is not taken for the determination of the mind, to pass from the idea of an object to that of its usual attendant.

knowledge

and

probability.

But though this be the only reasonable account we can give of necessity, the contrary notion is so riveted in the mind from the principles above-mentioned, that I doubt not but my sentiments will be treated by many as extravagant and ridiculous. What! the efficacy of causes lie in the determination of the mind! As if causes did not operate entirely independent of the mind, and would not continue their operation, even though there was no mind existent to contemplate them, or reason concerning them. Thought may well depend on causes for its operation, but not causes on thought. This is to reverse the order of nature, and make that secondary, which is really primary. To every operation there is a power proportioned; and this power must be placed on the body that operates. If we remove the power from one cause, we must ascribe it to another: but to remove it from all causes, and bestow it on a being that is no ways related to the cause or effect, but by perceiving them, is a gross absurdity, and contrary to the most certain principles of human reason.

I can only reply to all these arguments, that the case is here much the same, as if a blind man should pretend to find a great many absurdities in the supposition, that the colour of scarlet is not the same with the sound of a trumpet, nor light the same with solidity. If we have really no idea of a power or efficacy in any object, or of any real connexion betwixt causes