off, if he would. The former admit of correction, from new observation, or from careful comparison of various observations, whether in relation to the same or different objects. The latter remain firm and unalterable, whatever pains may be taken to annihilate or modify them. Place their objects in what light you will, raise your doubts, and bring forth your strong reasons, still nature is true to her purpose, and these instinctive principles maintain their ground. Now, what we contend is, that a belief in the efficiency of second causes is one of these principles. It is early, deep, universal, and incapable of being eradicated-just as really and truly as the belief of causation, and of an external world. Men can be found, indeed, who deny them all; but do they not contradict the voice of nature, if that voice can be learned from the sentiments of mankind in all ages and nations? Nay, do they not contradict the inward convictions of their own minds, if their actions can be taken as a true index of their convictions?

That fire fuses metals, and water melts salt, are facts, we have said, which no man can disprove; but are we not entitled to say, that they are facts which every man, from the very constitution of his mind, is compelled to believe? Can he any more doubt, that it is a quality of fire to fuse metals, and of water to melt salt, than he can doubt the existence of the substances of which these qualities are predicated? But Berkeley, it may be said, doubted both; he believed in no material substances or qualities, nor in anything which may be denominated an external world. True, such was his theory; but what was his practice? Did he act upon his own principles ? His philosophy said there was no external world; that what we call sensible things are merely our own sensations, produced by no external object, but by the immediate agency of God. But did he believe this when he attempted to argue with his fellow-men, whom he must

have considered as existing without, while yet he had no greater evidence of their existence than of other physical objects around him, and no evidence at all, but upon the testimony of sense.

Into a like inconsistency do they fall, who deny the efficiency of second causes; for, while they profess to regard them as powerless, they act towards them every moment as if they believed them possessed of an inherent and unremitting energy.

The whole of the preceding argument goes upon the principle that the efficiency of second causes is a commonsense notion, deeply engraven upon the human mind, and showing itself in the very structure of language, not only in modifying some of its less essential forms, but in giving birth to first principles, and shaping the very groundwork. Nor can we readily be persuaded that a sentiment at once so radical and universal can be accounted for, but by supposing it a dictate of nature, the result of that reason and common understanding which God has bestowed upon mankind.

[NOTE A.] The sentiment advanced in this place, and in other parts of the Lecture is, that whatever is regarded as the regular antecedent of any change, is instantly recognized by the mind as the efficient cause of the change; and that this is the unbiased voice of reason, or the dictate of common sense, from which there lies no appeal. If this statement be correct, it cannot fail to be perceived, that the efficiency of second causes is placed on as firm a basis as the doctrine of cause and effect, or the fact of an external world. To this statement, however, it has been objected that the supposed antecedent is not always the real antecedent; of course, that the mind is sometimes mistaken in its reference, regarding that as the proximate cause which, in fact, is not that cause. Will not this abate our con

fidence in the argument for the efficiency of second causes, drawn from the common and prevailing sentiment, that the known or supposed antecedent is truly an efficient cause? If the mind may mistake in its reference in one case, why not in another? if it does not intuitively and universally detect the true efficient in the case, how can we be sure that its dictates are not wholly fallacious?

Our reply is, that though the mind may mistake as to the proximate cause of a change, it does not thence follow, that it mistakes as to the efficiency of the cause to which the change is referred. The mistake lies in the proximity of the cause to the effect, not in the productive power of the cause, to which the effect is attributed. The common opinion is, that fire fuses metals, and water melts salt; but suppose it was ascertained that these substances produce their respective results through

the intervention of a medium or principle not heretofore discovered? Their powers would not be less real, but their agency would be less immediate than is now generally supposed.

Or take another example. Every man believes that his will is concerned as a cause in the free and unconstrained motion of his hand. He considers the muscles of this organ as obedient to his will, and subjected to his control. Nor is his belief, as to the efficiency of his will, in any measure altered, when he learns that the affection of the nerves connected with the organ constitutes another link in the chain. According to his first impression, his volition was the immediate antecedent to the contraction of the muscles which give motion to the hand. Now he finds the affection of the nerves as prior to that contraction, and necessary to its occurBut though the train is lengthened, the causes concerned are not less efficient, nor does he ascribe less power to his will.

rence.

LECTURE VII.

ON SECOND CAUSES.

ARE SECOND CAUSES EFFICIENT CAUSES?

In the preceding Lecture, we adverted to the different answers which had been given to this question; and stated that before the time of Descartes, all mankind, both learned and unlearned, believed second causes to be efficient, producing the changes which they seem to produce that since that period, many philosophers have professed to regard them as powerless, and the mere antecedents or signs of change.

We examined, at some length, the opinion of Dr. Reid and Professor Stewart, who maintain the efficiency of second causes in the moral, but deny it in the physical world. We attempted to show that their doctrine was unsupported by facts, and incompatible with itself; and that, to be consistent on this subject, we must adopt one of two propositions, either that second causes have power in both worlds, or in neither world; or, which comes to the same thing, either that God is the only efficient cause in the universe-producing by his immediate agency all the changes we see-or that second causes have power, and as truly in matter as in mind.

We adopted the latter proposition, and alleged in favor of it the well-known fact that mankind, from the

earliest records of time, have steadily acted under the full conviction of its truth. The very structure of language, aside from historical testimony, we considered as an unanswerable proof of such conviction. In short, that so deep and radical is this sentiment-so completely inwrought in the very first principles of language—that no man can make himself understood without employing terms which fully involve it. From this important fact we deduced the inference, that the efficiency of second causes has a strong claim to be considered a common sense notion, not unlike the general notion of cause and effect, or the belief of an external world.

Second. We remark now, that it seems difficult to conceive how men should ever arrive at the notion of cause and effect as an abstract relation, or at the belief of anything without them, or besides them, unless they went upon the principle that second causes have power. For if these notions are not born with them, nor communicated by special revelation, (neither of which will be pretended,) they must be acquired in the exercise of the mental faculties, either with or without the aid of the bodily powers. So far as I know, it is an admitted fact that the notion of a cause first arises in the mind on observing some change, and remarking the circumstances in which this change has occurred.

That we require the idea of antecedent and consequent in this way, and of the more general relation of regular antecedence and of regular consequence, seems to admit of no doubt. Nor will it be questioned, I suppose, that the idea of particular antecedence is obtained before the idea of general or uniform antecedence. Why should not all this be true, with respect to cause and effect? Can it be believed that men have the abstract notion of cause, and that no effect can take place without a cause, before they have learned what a cause is, through the medium of some change in a particular case? or, which